(concurring) :
To the discussion in our opinion drafted by Judge LEVENTHAL, supra, of last signatory employment requirements in connection with other eligibility requirements I merely wish to point out that while such provisions may not be illegal because of ameliorating provisions in certain pension plans, in other plans where they cause inequitable forfeitures, they may operate as an instrument of great inequity and oppression to some workers whose labor has caused very substantial contributions to be made to the fund. It seems to me that a mature pension fund drafted in the interests of the workers would base benefits chiefly on contributory employment and would provide for some partial vesting after substantial periods of contributory employment. It is recognized that the establishment of such a plan might require gradual changes over a period of years but it seems that it is an objective devoutly to be wished.