Historical Rules · 1 October 2009
Rule 117.7
Official source text from the 1 October 2009 Rules release
If an effect says that a player can't gain life, that player can't exchange life totals with a player who has a higher life total; in that case, the exchange won't happen. In addition, a cost that involves having that player gain life can't be paid, and a replacement effect that would replace a life gain event affecting that player won't do anything.