Cramer on Tuesday had a strong message for his viewers regarding BHP Billiton’s attempted buyout of Potash: His regular rules for owning takeover targets do not apply in this case.

Cramer typically recommends the selling of any company that has received a takeover bid on the idea that the upside in these situations is capped. But he can think of a bunch of reasons—four, in fact—why investors should hold onto Potash .