Most stocks gained ground on Tuesday, rallying on news that housing prices continue on their upswing. November saw the largest housing price increases in more than six years, and the S&P 500 Index (SNPINDEX:^GSPC) responded accordingly, rallying 7.7 points, or 0.51%, to close at 1,507. But even good times see struggling companies, and today was no different. Let's look at today's three worst S&P 500 stocks, which all managed to fall mightily on a generally bullish day.

Shares in disk-drive maker Seagate Technology (NASDAQ:STX) got pummeled by 9.4% after reporting earnings. Surprisingly, it wasn't even poor earnings but rather a dismal forecast that did the stock in. The company said it expected sales on the high end of $3.45 billion this quarter, below the $3.48 billion analysts expected and miles away from the $4.45 billion the company saw just a year ago. Ouch. 

Enterprise software provider BMC Software (UNKNOWN:BMC.DL) saw a 6.2% decline in its stock price Tuesday after a dismal earnings release. Results that were far below expectations spurred renewed talks about the future of the company, which has been in doubt since the spring of last year. The debate centers on whether BMC should be put up for sale or remain its own independent entity. 

Finally, in a strange situation on Tuesday, solar-panel company First Solar (NASDAQ:FSLR) declined 5.9% after a bizarre "offer" from a private securities firm to buy a portion of the company's stock for below market value. TRC Capital offered to buy out small-time investors in First Solar for $30 per share, below the $31.58 opening price of the stock. TRC said the offer is intended for shareholders with fewer than 100 shares; the company claims that such holders are often subject to higher trading fees and would benefit from accepting the generous price tendered by the private Toronto firm.

Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter, @divinebizkid, and on Motley Fool CAPS, @TMFDivine.

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