Apple (NASDAQ:AAPL) investors woke up to strong gains this morning, with shares jumping as much as $15.41 during trading today. The catalyst appears to be an analyst upgrade from Societe Generale, which boosted its rating from Hold to Buy. Analyst Andy Perkins also increased Apple's price target from $500 to $575.

Perkins' optimism stems from data suggesting that Apple is seeing continued momentum with sales of its new iPhones, and is modeling for Apple to beat Street forecasts as well as its own guidance in the fiscal fourth quarter.

The upgrade comes just a day before Apple hosts its iPad event, and Apple shares are notoriously susceptible to the "buy the rumor, sell the news" phenomenon. Investors could also just be excited to see what Apple has in store.

In this segment of Tech Teardown, Erin Kennedy discusses Apple's upgrade with Evan Niu, CFA.

Erin Kennedy and Evan Niu, CFA, both own shares of Apple. The Motley Fool recommends and owns shares of Apple. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.