(Dow Jones) Some advisors are concluding that BP PLC, which just a few months ago seemed like a blue chip, is just too risky for their clients.

The giant British oil company, with a 100-year history and a $10.5 billion annual dividend, has seen its shares plunge by roughly half in a matter of weeks as oil from a well deep underwater gushes into the Gulf of Mexico. No one seems able to say for sure when it will stop, much less what the cleanup will ultimately cost.

"Before the oil spill, BP was a good long-term holding," said Keith Amburgey, a financial planner in Cresskill, N.J. "After the spill, the stock became a short-term speculative play."

Amburgey said his firm began selling BP stock in early May, about two weeks after the rig explosion, eliminating BP holdings some clients had owned for years. By that point, he said, it had started to become clear questions about the incident were going to influence the price of the stock for a very long time. Although he personally suspects the market has overreacted, BP's legal and political jeopardy changed the risks and rewards of owning its shares for his buy-and-hold clients.

He likened the crisis to ones that have engulfed other seemingly impregnable companies recently, like Toyota Motor Corp., with its headline-making recall because of faulty brakes, and Goldman Sachs Group Inc., tarred by government charges over its business practices.

"This event served as a reminder of the benefits of diversification," he added.

Some large brokerage firms have made moves too. Wells Fargo Advisors said it removed BP from its Diversified Stock Income Plan, a list of stocks with attractive yields and good prospects for hiking dividends that it provides to clients. Meanwhile, Wells's sector analyst also advised conservative investors to consider other, less volatile energy stocks, according to a spokeswoman.

UBS AG said it helped arrange a recent discussion between its clients and BP investor relations officials. UBS's United Kingdom research department, which covers BP, published its seventh update on the spill situation Monday. Although UBS still rates BP a buy, the note warned investors should be prepared for BP not to make its July dividend payment if U.S. political pressure intensifies.

For some, the BP debacle is a chance to make lemonade out of lemons. Bryan Wisda, a financial planner with offices in Scottsdale, Ariz., said he has several clients with big positions in BP, such as one accumulated by a longtime employee of Amoco, the U.S. oil company BP acquired in 1998.

While the BP positions never fit well with Wisda's passive-oriented investment philosophy, he had been afraid that selling the holdings would generate an unnecessary capital gain for tax purposes. Now Wisda has been searching through the clients' accounts for lots of stocks that were purchased at prices equivalent to BP's current one and therefore can be unloaded without a tax hit.

While he concedes BP could snap back, he doesn't think trying to make that risky call is in his clients' best interest.

"It's betting," he said. "Investing isn't really a bettor's game."

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