"Position limits" are hard limits that an entity's ownership or control position may not exceed without potentially violating the CEA. "Accountability levels" are position levels that if exceeded, may trigger additional regulatory scrutiny and requests for information concerning the positions. Exceeding accountability levels is not a violation of the CEA; accountability levels are a regulatory tool to identify and monitor positions that reach a certain size and do not preclude maintaining or adding to the position. "Position accountability rules" apply to contracts that are less likely to be susceptible to the threat of manipulation. Under CFTC Rule 150.5(e), contracts that have an established trading history significant open interest and trading volume, have liquid cash and futures markets, and are readily arbitraged, may be subject to a position accountability rule, requiring reporting to the regulators, rather than a hard position limit.