NEW YORK ( TheStreet) -- Shares of Anadarko Petroleum were off by 3% on Tuesday and there was no shortage of potential catalysts for the decline. The best reason though may simply be that the oil rally was good while it lasted. The company announced before the open that its CEO James Hackett plans to retire and named COO Al Walker as his successor. JPMorgan Chase downgraded Anadarko from a buy to hold as well on Tuesday though the firm's call was unrelated to the management change. JPMorgan says a lawsuit involving the spinoff of a bankrupt company called Tronox could be an overhang on shares. On the management issue, if it was a surprise announcement, it's not a surprise replacement, and Hackett has always been expected to give up the reins at some point, even if this was a little earlier than expected. As Argus Research analyst Phil Weiss said, Walker has been responsible for some of the keys to the Anadarko turnaround in recent years. "Walker is the heir apparent and has been groomed for it. It doesn't seem like a reason to get rid of the stock," Weiss said. The Tronox case could be a potential liability to Anadarko, but the fact of the matter is that it's been an overhang on shares for years. Anadarko acquired chemicals company Kerr-McGee (of Silkwood infamy) and as part of the deal Tronox was spun off. Tronox went bankrupt and Anadarko is being charged with fraudulent conveyance -- a legal term that essentially means it spun off the company to shield it from the Tronox liabilities, or "convey" those liabilities to others, and those "others" being Tronox' shareholders, left holding the proverbial bag of a bankrupt entity. The Tronox case has been in the courts for years and Anadarko has had to list it as a potential liability in its SEC filings all along. A court trial is set to begin in May but other than that date approaching, there is nothing new about the Tronox situation. If it was a reason to sell Anadarko on Tuesday, it was a reason to sell Anadarko last week, last month, and last year as well.