<prompt> Human: More specifically, lets say youve got a diversified portfolio of 1M in your 401k. For whatever reason you want to move every penny of it all into one single fund. Then a month later you want to move it back into the same diversified funds you had it in before. Can you do that? What are the rules about how much, how often, etc. you can make fund transfers without any penalties or consequences.For purposes of this discussion, it doesnt matter if this is a good or a bad idea. Its just about the legalities of it.  <response>: Each fund has its own rules about excessive trading or length of time a fund must be held before a penalty fee applies. Then the financial company and your employer will have its rules about excessive trades.Outside of that, you can probably do that at least once or twice. Ive done multiple rebalances before being warned before. edit. Fidelity will warn you if the move you are about to make will trigger fees or other problems. 