Apple's operational expenditures on research and development activities surpassed $2 billion for the first time ever during the company's third fiscal quarter of 2015, a number equal to 4.1 percent of total net sales.

Compared to last quarter, Apple's R&D outlay for the quarter ending June jumped roughly $116 million to $2.03 billion, according to Apple's 8-K filing with the U.S. Securities and Exchange Commission. During the same time last year, spending stood at $1.6 billion, meaning money allotted to work on future products and services grew 21 percent year-over-year.

Apple, well known for its highly secretive R&D operations, first cracked the $1B spending mark in the last calendar quarter of 2012 and consistently piled on allotments quarter after quarter. The most obvious results of these asset expenditures are seen in Apple's consumer devices. For example, the company's latest Apple Watch product was in development for years before being announced to the public.

For the June quarter, spending is likely linked at least in part to impending iPhone and iPad product refreshes due out in fall. Apple is rumored to integrate Apple Watch's pressure-sensitive Force Touch screen technology into a next-generation iPhone model, though insiders claim low yield rates could affect initial launch supply.

Adding to Apple's bottom line are R&D centers strategically positioned in tech industry hot spots around the world, the latest venture being Japanese facility in Yokohama scheduled to open sometime next year. Reports say Apple is looking to draw experts in vehicle and health technology from the rich local talent pool.