With Apple expected to unveil its next-generation iPhone - widely referred to as iPhone 5 -, and probably even the iPad Mini, at its press event on Wednesday, September 12, there are speculations galore that the company will put to test the investor maxim "buy on the rumor, sell on the news", as investors will likely trade against how well the devices are received and on their sales projections.

Already, in anticipation of the expected unveiling of eagerly-awaited devices at the forthcoming event, the Apple stock touched a record 52-week high of $683.29 on Monday; with the company's shares having leaped nearly 16 percent since early June.

With Apple having had "an almost non-stop string of successes with product introductions" over the last few years, Jay Ritter - a University of Florida finance professor - said that the expectation of another successful device launch has prompted the market to bid up the price of the company's shares.

While Ritter also added that investors will stick with the "buy on the rumor, sell on the news" adage; Sandeep Dahiya - associate professor of finance at Georgetown University - said that pent-up demand for the next-generation iPhone is one strong indication for investors, even despite an increasing range of competitive devices from Samsung, Amazon, and Google.

Noting that "the news" would have to go beyond the expectations for the Apple stock to witness a rise on the launch day; Dahiya said: "Surprise is what moves the stock. Apple has a history of delivering good surprises."