The "Volcker rule," which is meant to limit speculative proprietary trading at major insured banks, appears at first glance to be fairly strict. However, experts said closer scrutiny of the rule reveals that it could be significantly watered down and that much would be left up to bank regulators. "There is a tremendous amount of discretion to bank agencies to come up with rules for the sparse language," said Richard Coll of DLA Piper. "The concepts are very general. In essence, the battle has now shifted to the rule making at the appropriate agencies."