A minor mystery lurks behind Anadarko Petroleum Corp.’s (APC) upcoming equity offering: Why does a company sitting on roughly $3 billion in cash need to raise money?

Anadarko’s total liquidity, including $4.5 billion in an undrawn credit facility, is $7.5 billion.

On June 3, Anadarko announced it would sell its midstream MLP along with interest potentially tied to its own shares, Simmons & Co. International said. The offerings would raise $450 million to $520 million before fees and expenses, analysts said.

Anadarko said the proceeds from the offering will be used for general corporate purposes.

The company is selling units in two Anadarko subsidiaries: Western Gas Equity Partners LP (WGP), formed to own partnership interests; and Western Gas Partners LP (WES), formed to acquire, own, develop and operate midstream energy assets.

The offerings are separate public offerings and neither offering is contingent on the completion of the other.

“While APC had previously indicated that they would methodically sell down their interest in WGP, the transaction is a bit surprising as a portion of the offering is potentially tied to APC's shares,” said David Kistler, co-head of E&P research, Simmons & Co.

Anadarko will sell, in total, 8.5 million units in Western Gas affiliates, with 6.5 million tangible equity units at $50 and 2 million WGP units that aren’t yet priced. Anadarko retains the right to deliver shares of its own common stock in lieu of WGP common units, said Andrew Coleman, analyst, Raymond James.

Following the 2 million WGP secondary offering, Anadarko will retain about 88% ownership of WGP, which had a $13 billion market cap as of June 4.

“While we believe the deal marks a move by Anadarko to unlock WGP value at the current market price, overall liquidity sees only a slight improvement for the company. As such, the deal is not a particularly material event for Anadarko,” Coleman said.

Western Gas Partners capex is estimated at up to $690 million in 2015, according to Anadarko.

Anadarko continues to be one of the prime E&P players with a 2015 capex of up to $6.4 billion. In April, the company closed its enhanced oil recovery (EOR) properties to Fleur de Lis Energy in the Powder River and Green River basins of Wyoming. In securities filings, Anadarko said proceeds for the sale were $703 million.

In March, the company also gained $1.5 billion from $2.64 billion in sale proceeds for the divestiture of a 10% working interest offshore Mozambique.

J.P. Morgan Securities LLC will serve as sole book-running manager for the TEU offering and lead book-running manager for the WGP secondary offering.