The Volcker plan appears to be an effort to force banks to choose--either be a traditional consumer-oriented bank or another type of bank that engages in proprietary trading and other activity that calls for the bank to put its own skin in the game. So who stands to be affected? Obviously, the big Wall Street powers.

According to Reuters, Goldman Sachs (GS) relies on trading (either agency or proprietary) for 55 percent of operating income. Morgan Stanley (MS) comes in at 36 percent, Barclays (18 percent), Bank of America (BAC) (12 percent), JP Morgan Chase (JPM) (12 percent), Citigroup (C) (9 percent), Bank of New York-Mellon (8 percent) and State Street (7 percent) follow. Separating out agency trades from proprietary trades may be possible but it would messy from a compliance standpoint. You would have to think that the big national consumer banks don't do a lot of prop trading, and you would have to assume Goldman Sachs will be willing to part with its bank charter. Morgan Stanley may have a tougher time. 

For more:
- here's the article

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