September 24, 1993
                  UNITED STATES COURT OF APPEALS
                       FOR THE FIRST CIRCUIT
                                            

   No. 92-2263
                         MONICA SANTIAGO,
                       Plaintiff, Appellant,

                                v.

                 SHERWIN WILLIAMS COMPANY, ET AL.,
                      Defendants, Appellees.
                                            

                           ERRATA SHEET

        Please make the following  correction in the opinion in
   the above case released on September 10, 1993:

   Page 7, footnote 4:  change the footnote to read as follows:

        Judge Breyer  dissents.  In his  view, despite the
        equitable arguments against certification  in this
        case,  in light  of the  importance of  the matter
        this panel should certify the issue to the Supreme
        Judicial Court.

                United States Court of Appeals
                    For the First Circuit
                                         

No. 92-2263

                       MONICA SANTIAGO,

                    Plaintiff, Appellant,

                              v.

              SHERWIN WILLIAMS COMPANY, ET AL.,

                    Defendants, Appellees.

                                         

         APPEAL FROM THE UNITED STATES DISTRICT COURT

              FOR THE DISTRICT OF MASSACHUSETTS

         [Hon. Joseph L. Tauro, U.S. District Judge]
                                                   

                                         

                            Before

                     Breyer, Chief Judge,
                                        
               Friedman,* Senior Circuit Judge,
                                              
                   and Stahl, Circuit Judge
                                           

                                         

Jonathan   Shapiro,  with   whom  Stern,   Shapiro,  Rosenfeld   &amp;
                                                                  
Weissberg,  Robert J. Doyle, Kehoe,  Doyle, Playter &amp;  Novick, Neil T.
                                                                  
Leifer, Thornton, Early &amp;  Naumes, Judith Somberg, Johnson  &amp; Somberg,
                                                                 
Arthur Bryant, and Trial Lawyers for Public Justice, were on brief for
                                               
appellant.
Paul  Michael Pohl, with whom Charles H.  Moellenberg, Jr., Jones,
                                                                  
Day, Reavis  &amp; Pogue, Thomas  J. Griffin, Jr., Loretta  Smith, Erik H.
                                                                  
Aldeborgh,  II, Goodwin, Procter &amp;  Hoar, Dale A.  Normington, were on
                                                         
brief  for  Sherwin-Williams  Company,  Rory  FitzPatrick,  Meghan  H.
                                                                  
Magruder,  Bingham, Dana &amp; Gould, Donald A.  Bright, were on brief for
                                               
Atlantic Richfield Company, Michael Nilan, G. Marc Whitehead, Janie S.
                                                                  
Mayeron, Popham, Haik,  Schnobrich &amp;  Kaufman, Ltd.,  Thomas V.  Urmy,
                                                                 
Shapiro, Grace  &amp; Haber, were on brief  for SCM Corporation, Donald E.
                                                                  
Scott, John M. Walker, Kirkland &amp; Ellis, David B. Garten, and Janet D.
                                                                  
Smith,  were  on brief  for NL  Industries,  Inc., and  Mary Morrissey
                                                                  

Sullivan, Richard Nahigian,  and Sullivan, Sullivan  &amp; Pinta, were  on
                                                        
brief for Lead Industries Association.
David G. Owen on  brief for The Business Roundtable and Chamber of
             
Commerce of the United States of America, amici curiae.
Stephen  S. Ostrach,  Emily R.  Livingston and  New England  Legal
                                                                  
Foundation on brief for Associated Industries of Massachusetts and New
      
England Legal Foundation, amici curiae.

                                         

                      September 10, 1993
                                         

                
*Of the Federal Circuit, sitting by designation.

          STAHL, Circuit Judge.   In this appeal,  plaintiff-
                              

appellant Monica  Santiago  challenges the  district  court's

entry  of  summary  judgment  against her  and  in  favor  of

defendants-appellees.1    In  so  doing,  plaintiff  advances

three  arguments:  (1) the legal issues in this appeal should

be  certified to  the  Massachusetts  Supreme Judicial  Court

("SJC");   (2)  the   district  court   erred  in   rejecting

plaintiff's  market  share liability  argument;  and  (3) the

court erred in rejecting plaintiff's concert of action claim.

After carefully  reviewing each of  plaintiff's arguments, we

affirm.

                              I.
                                

                          BACKGROUND
                                    

          Plaintiff was born  on November 9, 1972.   From the

time of  her birth until 1978, she  and her family resided at

20  Leston Street in Boston.   Plaintiff alleges that, during

her  period of residence,  she ingested  lead paint  that had

been applied in layers to the walls and woodwork of her  home

at various times  between 1917,  the year  of the  building's

construction,   and  1970.     The   evidence  reveals   that

                    

1Defendants  are  Sherwin-Williams  Company,  NL  Industries,
Inc.,  Eagle-Picher  Industries,  Inc.,   Atlantic  Richfield
Corporation (successor  to International Smelting  &amp; Refining
Company), and SCM Corporation (successor to Glidden Company).
On   January  7,  1991,   defendant  Eagle-Picher  filed  for
bankruptcy in  Ohio, thus  automatically staying  this action
against it.  See 11 U.S.C.   362.
                

                             -3-

plaintiff's blood had highly  elevated levels of lead  by the

time plaintiff was  one year  of age, that  the lead  reached

emergency levels  by July 1976,  and that, as  a consequence,

plaintiff  had  to undergo  chelation  therapy2  in order  to

remove the  lead from her  body.  Although  plaintiff's early

development  appeared  to  progress normally,  she  has  been

diagnosed with a  hyperactivity-attention disorder and  motor

skill  difficulties  which her  medical experts  attribute to

lead poisoning.

          Plaintiff initiated this  action in November  1987,

contending   that  defendants,   or  their   predecessors  in

interest, manufactured and marketed all, or virtually all, of

the  white lead  used in the  lead paints sold  in the United

States between 1917 and 1970.  Her complaint set forth claims

of  negligence, breach  of warranty,  and concert  of action.

Jurisdiction was premised upon diversity of citizenship.  See
                                                             

28 U.S.C.   1332.

          Plaintiff  could  not  and cannot  identify  either

which,  if any, of the defendants are  the source of the lead

she  ingested or  when the  alleged injury-causing  paint may

have  been applied to the walls and woodwork of her childhood

                    

2Chelation therapy is a procedure whereby a person  with lead
poisoning  is  given  chemicals  that  bind  with  the  lead,
enabling the body to excrete it more rapidly.

                             -4-

home.3    She has,  however, introduced  (1) evidence  in the

form  of expert testimony that  lead paint "was  at minimum a

substantial contributing  factor of her  lead poisoning;" (2)

evidence  demonstrating that  all of the  defendants produced

white  lead for  significant portions  of the  period between

1917 and 1970; (3) evidence that almost all of the white lead

produced for paint  between 1917 and 1970 was manufactured by

defendants; and (4) evidence that, between 1930 and 1945, all

of the defendants, as members of a trade association known as

the  Lead  Industries  Association  ("LIA"),  "simultaneously

coordinat[ed]  promotional campaigns  to increase  white lead

consumption in paint  and .  . . work[ed]  to neutralize  the

growing public  concern about lead paint poisoning."   On the

basis of this evidence, plaintiff sought to dispense with the

identification requirement and hold defendants liable under a

market   share  theory.     Plaintiff  further   argued  that

defendants  were liable  for  her injuries  because of  their

concerted marketing actions as members of the LIA.

          By memorandum and order dated January 13, 1992, the

district court  rejected plaintiff's market share  claim as a

matter  of Massachusetts law.   In so doing,  the court ruled

                    

3There is no direct evidence that plaintiff actually ate lead
                   
paint.  There is,  moreover, record evidence suggesting that,
in addition to lead paint,  plaintiff could have been exposed
to  airborne lead, lead from food and water, and/or lead from
soil and  dust.  Indeed,  there is  evidence indicating  that
plaintiff's neighborhood, including the soil around her home,
was heavily contaminated with lead.

                             -5-

that even if the  SJC would recognize market  share liability

under some scenario, it would not do so if presented with the

undisputed facts  of this  case.   See generally  Santiago v.
                                                          

Sherwin-Williams Co., 782 F.  Supp. 186 (D. Mass. 1992).   By
                    

memorandum and  order dated July  2, 1992, the  court further

ruled that  plaintiff's concert of  action claim failed  as a

matter  of  Massachusetts  law because  plaintiff  could  not

identify which  of the defendants actually  had committed the

tort.  See generally Santiago v. Sherwin-Williams Co., 794 F.
                                                     

Supp.  29 (D.  Mass. 1992).   It is  from these  rulings that

plaintiff now appeals.

                             II.
                                

                          DISCUSSION
                                    

A.  Certification
                 

          As an initial matter, plaintiff  has requested that

we certify to  the SJC questions  regarding the viability  of

market share liability and concert  of action as theories  of

recovery in  light of the facts  of this case.   We note that

plaintiff first  requested certification  in this court,  and

explicitly  stated her  opposition  to  certification at  the
                                  

district court level.  Now,  having lost below, plaintiff has

reversed  her  position.  Unsurprisingly,  defendants  oppose

plaintiff's certification request.

          For reasons  that are largely  self-explanatory, we

have  held  that "one  who  chooses to  litigate  [her] state

                             -6-

action  in  the federal  forum (as  plaintiff did  here) must

ordinarily    accept    the   federal    court's   reasonable

interpretation  of  extant  state  law  rather  than  seeking

extensions via  the certification process."   Croteau v. Olin
                                                             

Corp., 884 F.2d  45, 46 (1st Cir. 1989); see also 17A Charles
                                                 

A. Wright,  Arthur R. Miller,  and Edward H.  Cooper, Federal
                                                             

Practice  and Procedure    4248,  176 (2d  ed.  1988) (courts
                       

"should be slow to  honor a request for certification  from a

party  who  chose  to  invoke federal  jurisdiction").    The

concerns about fundamental fairness and judicial economy that

animate this general rule  make us considerably less inclined

to  depart  from  it  when  the  plaintiff  did  not  request

certification before  the district  court.  See  Croteau, 884
                                                        

F.2d at 46.

          Here, as will  be demonstrated below, the  district

court's  interpretation  of Massachusetts  law  was eminently

reasonable.  Furthermore, plaintiff, after initially deciding

to eschew her prerogative to file this action in state court,

actively made  her opposition  to certification known  to the

district  court.   In  light of  these  facts, and  given the

further fact that  it has  been over five  years since  these

federal  proceedings  were initiated,  it would  be extremely

unfair  to  defendants  if  we were  to  allow  plaintiff  to

relitigate  the   issues  at  the  heart   of  this  lawsuit.

                             -7-

Accordingly,   plaintiff's   request  for   certification  is

denied.4

B.  Standard of Review
                      

          Having  dispensed  with  plaintiff's  certification

request,  we  proceed  to  delineate the  parameters  of  our

examination.   Summary judgment allows courts  to "pierce the

boilerplate of the  pleadings and assay the parties' proof in

order  to  determine  whether  trial is  actually  required."

Wynne v. Tufts Univ. Sch. of Medicine, 976 F.2d 791, 794 (1st
                                     

Cir.  1992), cert. denied, 113 S. Ct. 1845 (1993).  It should
                         

be granted  when  "the  pleadings,  depositions,  answers  to

interrogatories, and  admissions on  file, together with  the

affidavits, if any, show that there is no genuine issue as to

any  material fact and that  the moving party  is entitled to

judgment as a matter of law."  Fed. R. Civ. P. 56(c).

          A fact is only material if it has "the potential to

affect  the outcome of  the suit  under the  applicable law."

Nereida-Gonzalez  v. Tirado-Delgado,  990 F.2d 701,  703 (1st
                                   

Cir.  1993).  However, our  reading of the  facts, as derived

from the record, is  always done "`in the light  most amiable

to  the nonmovant. . .  .'"  Lawrence  v. Northrop Corp., 980
                                                        

F.2d  66, 68 (1st Cir.  1992) (quoting Garside  v. Osco Drug,
                                                             

                    

4Judge Breyer dissents.   In his view, despite  the equitable
arguments against certification in this case, in light of the
importance  of the matter this panel should certify the issue
to the Supreme Judicial Court.

                             -8-

Inc.,  895 F.2d  46,  48 (1st  Cir.  1990)).   This  includes
    

"indulg[ing]  all reasonable  inferences" in  the nonmovant's

favor.  Id.
           

          Our review of a summary judgment ruling is plenary.

Garside, 895 F.2d  at 48.  Furthermore, we are not limited to
       

the reasoning employed by the district court; instead, we may

"affirm the  entry of  summary judgment on  any independently

sufficient  ground  made manifest  by  the  record."   United
                                                             

States v. One Parcel of Real Property, 960 F.2d 200, 204 (1st
                                     

Cir. 1992).

          In addition to examining the facts, a court passing

on a summary judgment motion  or reviewing a summary judgment

determination must,  of course, consider the  applicable law.

When a  plaintiff invokes  diversity jurisdiction to  bring a

state law  claim in federal  court, this  survey is  somewhat

circumscribed,  for   it   is  settled   that,  in   ordinary

circumstances, a  plaintiff who  "selects a federal  forum in

preference  to an  available state  forum may not  expect the

federal  court   to  steer   state  law  into   unprecedented

configurations."   Martel  v. Stafford,  992 F.2d  1244, 1247
                                      

(1st  Cir. 1993); see also  Ryan v. Royal  Ins. Co., 916 F.2d
                                                   

731, 744  (1st Cir. 1990) (rejecting  a diversity plaintiff's

attempt  to stretch  New York  law to  new frontiers  without

providing a "well-plotted roadmap showing an avenue of relief

that the state's highest  court would likely follow"); Porter
                                                             

                             -9-

v. Nutter, 913  F.2d 37,  41 (1st Cir.  1990) (plaintiff  who
         

seeks out a federal venue in a diversity action should expect

"unadventurous" interpretations  of state law).   Mindful  of

these strictures, we turn to plaintiff's claims.

C.  Market Share Liability
                          

          Plaintiff argues  that the district court  erred in

granting defendants summary judgment  on her claim for market

share liability.  In  so doing, she concedes that the SJC has

never explicitly endorsed a  market share liability theory of

recovery, and  further recognizes  that the court  rejected a

certain   species  of  market  share  liability  advanced  by

plaintiffs  in  a DES  class action.    See Payton  v. Abbott
                                                             

Labs., 437  N.E.2d 171,  188-90 (Mass. 1982).5   Nonetheless,
     

                    

5In  Payton,  an action  brought by  a  class of  women whose
           
mothers  ingested DES  while pregnant  with them,  the United
States District  Court  for  the  District  of  Massachusetts
certified to the SJC the following question:

          Assuming that the evidence does not  warrant a
     conclusion that the defendants  conspired together,
     or  engaged in  concerted  action,  or  established
     safety standards  through a trade  association, may
     the defendant manufacturers, who  probably supplied
     some  of  the DES  ingested by  the mothers  of the
     plaintiff class,  be held liable to  members of the
     plaintiff class when neither the plaintiffs nor the
     defendants  can  identify which  manufacturer's DES
     was ingested by which mothers?

Id.  at 188.   The  SJC ruled  that it  could not  answer the
   
question in the form  stated because the question "d[id]  not
explicitly  assume  that  the  plaintiffs  will  be  able  to
establish the negligence of . . . defendants."  Id.  However,
                                                   
as is discussed more fully below, the court did set forth its
general views on  market share  liability.  In  so doing,  it
rejected  the theory  of market  share liability  advanced by

                             -10-

plaintiff asserts that certain  dicta in Payton indicate that
                                               

her claim would be approved by the SJC.6  We cannot agree.

          As  the SJC  has  noted, "[i]dentification  of  the

party  responsible  for  causing   injury  to  another  is  a

longstanding prerequisite to a successful negligence action."

Payton,  437 N.E.2d at 188.   However, some courts, cognizant
      

of the modern  industrial reality of fungible goods which may

harm  consumers  but  which  cannot  be  traced  to  specific

producers,  have relaxed  this identification  requirement in

certain  negligence and  product liability  cases.   In these

cases, the courts  have allowed plaintiffs who are  unable to

identify the  particular defendant who  actually manufactured

the harm-causing product  to pursue their  claims so long  as

they are able to prove both  that the product caused the harm

and that  the defendants were  market suppliers  at the  time

plaintiff  had her harmful encounter  with the product.  See,
                                                            

                    

plaintiffs in that case.  Id. at 189.
                             

6In concluding its  explicit rejection of the  form of market
share liability plaintiffs sought to impose, the Payton court
                                                       
stated:

          That is not  to say that on an adequate record
     this court  would not recognize  some relaxation of
     the   traditional  identification   requirement  in
     appropriate circumstances so  as to allow  recovery
     against a negligent defendant  of that portion of a
     plaintiff's damages  which  is represented  by  the
     defendant's  contribution of DES  to the  market in
     the relevant period of time.

Id. at 190.
   

                             -11-

e.g., Sindell v. Abbott  Labs., 607 P.2d 924,  936-38 (Cal.),
                              

cert. denied, 449 U.S.  912 (1980).  If a  plaintiff prevails
            

in  such   a  case,   courts  typically  have   limited  each

defendant's  liability  to that  portion  of the  plaintiff's

judgment which reflects  the share of the  market supplied by

the defendant at the time of said encounter.  See, e.g., id.,
                                                            

607 P.2d at 937.  Market share liability has most often  been

recognized in the context of DES cases.  See, e.g., McCormack
                                                             

v. Abbott Labs., 617 F. Supp. 1521 (D. Mass. 1985); McElhaney
                                                             

v. Eli Lilly &amp; Co., 564 F. Supp. 265 (D.S.D. 1983); Conley v.
                                                          

Boyle  Drug Co., 570 So.2d  275 (Fla. 1990);  Hymowitz v. Eli
                                                             

Lilly &amp; Co., 539  N.E.2d 1069 (N.Y.), cert. denied,  493 U.S.
                                                  

944  (1989);  Martin v.  Abbott  Labs., 689  P.2d  368 (Wash.
                                      

1984);  Collins v.  Eli Lilly  &amp; Co.,  342 N.W.2d  37 (Wis.),
                                    

cert. denied, 469  U.S. 826 (1984).   But see  Ray v.  Cutter
                                                             

Labs.,  754 F. Supp. 193  (M.D. Fla. 1991) (product contained
     

HIV virus); Morris v.  Parke, Davis &amp; Co., 667 F.  Supp. 1332
                                         

(C.D. Cal.  1987) (plaintiff harmed by DPT vaccine); Smith v.
                                                          

Cutter Biological,  Inc., 823  P.2d 717 (Haw.  1991) (product
                        

contained HIV virus).

          As  noted  above,  the  SJC did  have  occasion  to

consider, by means of a certified question, the viability  of

one  form of  market  share liability  in  a DES  case.   See
                                                             

Payton,  437 N.E.2d at 188-90.   In Payton, plaintiffs argued
                                          

for market share  liability with two significant twists:  (1)

                             -12-

that  they  be allowed  to proceed  against and  recover full

damages  from only  six named  DES manufacturers  despite the

fact that there was a larger number of potential tortfeasors,

and (2) that defendants  should be prohibited from presenting

exculpatory  proof.  See id.  at 188-89.   The court rebuffed
                            

these arguments, holding that two articulated reasons for the

identification  requirement,  (1)  that  wrongdoers  be  held

liable  only  for the  harm they  have  caused, and  (2) that

tortfeasors  be  separated  from  innocent  actors, would  be

disserved  by  the  adoption of  plaintiffs'  theory.   Id.  
                                                           

Accordingly, as we have  stated, the SJC rejected plaintiffs'

version of market share liability.  Id. at 189. 
                                       

          We  accept for  the  sake  of argument  plaintiff's

assertions  (1) that  the SJC  would, in  some circumstances,

relax the identification requirement and allow a plaintiff to

recover under a market  share theory; (2) that the  SJC would

recognize  market  share  liability  in  the  lead  poisoning

context;  (3)   that  plaintiff  has   introduced  sufficient

evidence  for  a  reasonable  factfinder to  infer  that  her

injuries resulted  from lead  poisoning; (4) that  lead paint

was,  as  one of  plaintiff's experts  puts  it, at  least "a

substantial contributing factor  of her lead poisoning";  and

(5) that  defendants, who were  mere bulk suppliers  of white

lead and  did not manufacture  or market the  alleged injury-

causing  paint,  could  still   be  adjudged  to  have  acted

                             -13-

negligently towards plaintiff.  Nonetheless,  we believe that

the  SJC's  professed  interest  in  both holding  wrongdoers

liable only for the  harm they have caused and  in separating

tortfeasors  from  innocent actors  is  fatal to  plaintiff's

claim.  

          Simply put, allowing plaintiff's market share claim

to proceed despite plaintiff's inability to pinpoint with any

degree  of precision  the time  the injury-causing  paint was

applied  to the  house on  Leston Street  would significantly

undermine   both  of   the   articulated  reasons   for   the

identification  requirement.   The record before  us reflects

that the layers  of lead  paint were applied  to the  house's

walls at  various undeterminable points in  time between 1917

and 1970.7  It  also indicates that defendants' contributions

to  the lead  paint market  varied significantly  during this

time period.  Given  these facts, it is difficult  to discern

the basis upon which any market share  determination would be

premised.8  At  any rate, it is evident  that the adoption of

                    

7Plaintiff did introduce expert testimony  attempting to date
one of the multi-layered paint samples taken from  the house.
However, this expert  was only able to say that  one layer of
lead paint probably  was applied between  1933 and 1939,  and
that  a  second layer  of  lead  paint was  probably  applied
between 1955 and 1969. 

8Apparently,  plaintiff would  have  market share  determined
according  to an  average of  defendants' market  shares over
time.  Because such  an approach would virtually  guarantee a
deviation between  liability and  actual culpability  for all
the named  defendants, we  are confident that  the SJC  would
look upon it with disfavor.

                             -14-

plaintiff's  theory would  not be  consistent with  the SJC's

admonition that wrongdoers  be held liable only for  the harm

they have caused.

          Moreover, several of the defendants were not in the

white lead pigment market at  all for significant portions of

the  period between 1917 and 1970, and therefore may well not

have  been market  suppliers at  the time  the injury-causing

paint was applied to the walls of plaintiff's home.  This, of

course,   raises  a   substantial   possibility  that   these

defendants not only could  be held liable for more  harm than

they actually caused, but also could be held liable when they

did not, in fact, cause any  harm to plaintiff at all.  Under

plaintiff's  theory,  therefore,  tortfeasors   and  innocent

actors would not be adequately separated.

          Finally,  we note  that  the dicta  relied upon  by

plaintiff  indicates that a  relaxation of the identification

requirement to  allow recovery against  a negligent defendant

would  only be  appropriate to  the extent that  the recovery

represents "that  portion of  a plaintiff's damages  which is

represented by  that defendant's  contribution . .  . to  the

market in the relevant period of time."  Id. at 190 (emphasis
                                            

supplied).   Here, as  noted, plaintiff cannot  identify with

adequate specificity the  relevant period of time.   Thus, it

appears that plaintiff's theory does not fall within even the

vague parameters mentioned in the SJC's dicta.

                             -15-

          In  sum,  allowing plaintiff  to  recover  her full

damages from the five  named defendants despite her inability

to specify the  time of  their negligence may  well, on  this

record, do violence to the SJC's stated interest in  ensuring

that  wrongdoers be held liable  only for the  harm they have

caused.  It also would create a substantial  possibility that

tortfeasors   and  innocent  actors  would  be  impermissibly

intermingled.  The SJC  has made it abundantly clear  that it

would  not countenance either  result.   Accordingly, mindful

that  federal courts  sitting in  diversity at  a plaintiff's

election  ought  not  "steer  state  law  into  unprecedented

configurations," see Martel, 992 F.2d  at 1244, we affirm the
                           

district court's  grant of summary judgment  to defendants on

plaintiff's market share claim.9

D.  Concert of Action
                     

          Finally, plaintiff contends that the district court

erred in granting defendants  summary judgment on her concert

of action claim.  Again, we cannot agree.

                    

9We are aware that  the United States District Court  for the
District of  Massachusetts, relying  on the dicta  in Payton,
                                                            
approved a market  share theory  of recovery in  a DES  case.
See McCormack, 617 F. Supp. at 1525-26.  We note simply  that
             
the  McCormack case was never  appealed and that  we have not
              
had, nor do we  now have, occasion to pass on the correctness
of its holding.  We further note that the aspect of this case
upon which we rest our preclusion of plaintiff's market share
claim  --  plaintiff's  inability  to identify  the  time  of
defendants'  alleged   negligence  --  was   not  present  in
McCormack.
         

                             -16-

          Plaintiff's  concert  of action  claim  is premised

upon the  theory of liability set forth in Section 876 of the

Restatement  (Second) of  Torts  (1977).   In relevant  part,

Section 876 (entitled "Persons Acting in Concert") provides:

     For  harm  resulting to  a  third  person from  the
     tortious conduct  of  another, one  is  subject  to
     liability if he

       (a) does a tortious act in concert with the other
     or pursuant to a common design with him, or

       (b) knows  that the other's conduct constitutes a
     breach of duty and gives substantial  assistance or
     encouragement to the other  so to conduct himself .
     . . .

In   isolated   circumstances,   Massachusetts  courts   have

indicated their willingness to permit recovery under theories

tracking the  language of  Section  876.   E.g., Orszulak  v.
                                                         

Bujnevicie, 243  N.E.2d 897,  898 (Mass. 1969)  ("Persons who
          

race automobiles on a public way are liable in negligence for

injuries  caused  by one  of  them."); Nelson  v.  Nason, 177
                                                        

N.E.2d 887, 888 (Mass. 1961) (similar).

          In essence, plaintiff claims that, "in light of the

substantial medical  evidence of  the unreasonable risk  that

[lead  paint]   posed  to   young  children[,]"   certain  of

defendants' actions  as members of  the LIA between  1930 and

1945  were  tortious.    Specifically,  plaintiff  points  to

defendants'    "initiat[ion   of]    nationwide   promotional

campaigns, encourage[ment of] the use of white lead  in house

paint  through extensive advertising, [attempts] to undermine

                             -17-

the growing medical evidence of the danger of lead paint, and

work[]  to prevent the  enactment of governmental regulations

which would have restricted the use of white lead in painting

buildings."10      What   is   utterly   lacking   from   her

presentation, however,  is any  evidence that these  actions,

during  the fifteen year period she  identifies, had any role
                                                        

in  causing lead  paint to  be  applied to  the walls  of her

childhood home.   Even if we assume that at least some of the

lead paint  consumed by  plaintiff was  applied  to her  home

during the  period of defendants'  alleged concerted actions,

there is no evidence that the application resulted from these
           

actions, or that it would not have taken place in the absence

of  these actions.  Cf. Roberts v. Southwick, 614 N.E.2d 659,
                                            

663  (Mass. 1993)  (endorsing instruction  defining proximate

cause  as "that which, in continuous  sequence, unbroken by a

new cause,  produces an  event, and  without which the  event

would not have  occurred").  Thus,  it is  our view that  the

factfinder  could  only have  based  a  causation finding  on

speculation or  conjecture.   Clearly, this is  inappropriate

under Massachusetts law.  See Goffredo v. Mercedes-Benz Truck
                                                             

Co., 520  N.E.2d 1315,  1317-18 (Mass.  1988); Gynan  v. Jeep
                                                             

Corp., 434 N.E.2d 688, 691 (Mass. App. Ct.) (plaintiff "could
     

not  leave causation merely  to speculation and conjecture"),

                    

10Plaintiff acknowledges,  however, that she has  no evidence
that  defendants  ever  concealed  information  or introduced
false research into public debate.

                             -18-

review denied, 440 N.E.2d 1177 (Mass. 1982); see also W. Page
                                                     

Keeton et  al., Prosser and Keeton on Torts   41, at 269 (5th
                                           

ed.  1984)  ("The  plaintiff  must  introduce  evidence which

affords a reasonable basis for the conclusion that it is more

likely than not that the conduct of the defendant was a cause

in fact of the result.  A  mere possibility of such causation

is  not enough;  and  when the  matter  remains one  of  pure

speculation or  conjecture, or the probabilities  are at best

evenly balanced, it becomes the duty of the court to direct a

verdict for the defendant.").

          We  acknowledge that  the question of  causation is

generally  for the  factfinder.   See Mullins  v. Pine  Manor
                                                             

College, 449 N.E.2d 331, 338 (Mass. 1983).  Where there is no
       

evidence from which the  factfinder, without speculating, can

find causation, however, the  case is appropriately kept from

the jury.  See Goffredo, 520 N.E.2d at 1318.  We believe that
                       

this is such  a case.   Accordingly, we  affirm the  district

court's  decision  to award  defendants  summary judgment  on

plaintiff's concert of action claim.11

                    

11We  recognize that  the  district court  based its  summary
judgment  decree on  the fact  that plaintiff  was unable  to
identify any  of the defendants specifically  as tortfeasors.
See  Santiago, 794  F. Supp. at  33.  We  also recognize that
             
plaintiff has  spent much effort challenging this ruling.  As
noted  above, however,  we are  free to  affirm the  entry of
summary judgment on any independently sufficient  ground made
manifest by the  record.   One Parcel of  Real Property,  960
                                                       
F.2d at  204.   Because we do  so here, we  do not  reach the
correctness of the district court's decision.

                             -19-

                             III.
                                 

                          CONCLUSION
                                    

          Because  certification to  the  SJC of  the  issues

raised in  this appeal  would  be inappropriate,  plaintiff's

request  therefor   is  denied.    Furthermore,  because  the

district court correctly ruled  that plaintiff's market share

and concert  of action  claims fail as  a matter  of law,  we

affirm  its  granting  of  defendants'  motions  for  summary

judgment thereon.

          Affirmed.  Costs to appellees.
                                       

                             -20-
