Fitch Ratings has placed 157 residential MBS classes serviced by Residential Capital on Rating Watch Negative as the ailing subsidiary of Ally Financial slid closer to bankruptcy. The rating action came on the heels of a Fitch downgrade of ResCaps issuer default rating to C from CCC on April 18. In addition, Fitch placed GMAC Mortgages servicer rating on Rating Watch shortly before the adverse rating action against ResCap. Fitch said the coordinated rating actions reflect the current uncertainty for the servicing portfolio due to the growing possibility of a bankruptcy or debt restructuring for...