Apple Inc. (NASDAQ: AAPL) filed its Q-10 report with the Securities and Exchange Commission (SEC) yesterday, a 68 page document that reveals a panoply of statistics about the technology giant’s operations during the quarter ending on December 28th, 2013.

One item in particular caught the notice of analysts and investors – Apple’s expenditure of $525 million on unspecified acquisitions during the period. This represents 184% of the sum spent on acquisitions in the same quarter in 2012, a massive rise in activity that may signal a major shift in the company’s focus or the groundwork for important new product lines.

One of Wells Fargo’s chief analysts, Maynard Um, identified a trio of purchases which he believes account for Apple’s (AAPL) extraordinary spending spree. The largest of these was the acquisition of PrimeSense, an Israel-based designer and manufacturer of motion sensor and 3D scanning devices. PrimeSense products are used for everything from motion-based game controller accessories to automated scanners used in health care.

Other probable purchases, according to Mr. Um, include the social media analysis specialist Topsy, and Cue, a company based around a popular iPhone app which aggregated various calendar and e-mail data to create a customized daily agenda. Cue’s acquisition was confirmed in October by TechCrunch, and was the smallest of the three major purchases.

These fourth quarter acquisitions followed a year during which Apple Inc. (AAPL) was exceptionally busy purchasing other companies. Their precise reasons for buying each company remain shrouded in secrecy, a standard procedure for the Cupertino, California enterprise. Among these procurements were BroadMap, a firm that produces digital mapping products and geospatial data analysis software, and Catch, an app maker specializing in mobile device apps for capturing and sharing data with work teams and other groups.

Dozens of other firms were also snapped up, including many working in the fields of location data, location mapping, transit, and navigation. Whether these purchases are related to Apple’s (AAPL) rumored release of fresh product ranges in 2014 remains to be seen, but the half-billion acquisition binge revealed in yesterday’s report is an intriguing capstone to a twelve month period studded with an unprecedented series of large-scale investments.

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