An outside accountant to Johnson & Johnson stockholders is battling a third-party lawsuit filed by Proskauer Rose that claims his accounting firm should be held fully liable for any damages allegedly suffered by shareholders after a tax avoidance strategy backfired.

Proskauer Rose itself is defending a $40 million fraud suit brought by Seward Johnson, Jr., the grandson of the company founder, his wife Joyce Johnson and two J&J trusts over legal advice that the firm provided in 2000 relating to the sale of company stock.