Shares in Apple Inc. leapt by more than four percent in heavy trading Thursday. In the early afternoon session, the stock was up more than four percent and knocking on the door of a US$500 per share price point.

Source: Yahoo! Finance

Wall Street seemed taken with a research note from Canaccord that estimated that Apple claimed more than 80 percent of all operating profits in the mobile handset industry. The Mac Observer is working on full coverage of that news.

Other news affecting the broader markets may have helped lift AAPL, as well. In Europe, Greece came to an agreement on austerity measures to help lead that country out of its debt crisis, while in the U.S., a better-than-expected unemployment report suggested that the U.S. economy is continuing to improve. Rounding out the positive news were indicators from major central banks in Europe that they would be holding interest rates at record lows.

All of those factors contributed to small gains on the three major indices in the U.S.

Shares in AAPL traded as high as $496.75 during the early afternoon session on Thursday. As of this writing, the stock had bounced off that high, but was still trading at $494.50, a gain of $17.82 (+3.74 percent), on heavy volume. That price gives the company a market cap of $461 billion, well ahead of the world’s second most valuable company, Exxon Mobil.

*In the interest of full disclosure, the author holds a tiny, almost insignificant share in AAPL stock that was not an influence in the creation of this article.