Apple has acquired 20 to 25 companies in the past six months, CEO Tim Cook told CNBC on Monday.

At that rate, the popular electronics company has bought a new company every two to three weeks.

But most of those acquisitions have been kept on the down-low, and many from the past six months haven't been announced.

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Apple has bought 20 to 25 companies in the past six months, according to CEO Tim Cook, but you probably haven't heard about most of them.

Cook's disclosure came during an interview with CNBC on Monday, in which he said the company mostly acquires for talent and intellectual property. He said that Apple buys a new company every two to three weeks on average.

Among those 20-plus acquisitions is Apple's December purchase of Platoon, a startup that works directly with musicians to produce and distribute their work. In March, Apple reportedly acquired an application-programming-interface-development startup called Stamplay.

But there are at least 14 Apple acquisitions unaccounted for.

Given Apple's market cap of $952 billion, most acquisitions the company makes are too small to be materially consequential, which means Apple doesn't have to disclose the purchases or any information about the buying processes of them.

Here are the Apple acquisitions since November that we know about:

The company has $225 billion in cash and securities on its balance sheet, according to its most recent earnings, which makes Apple one of the most cash-rich enterprises in tech. It also means Apple has a lot of opportunities and incentive to spend.

But unlike the tech giant IBM, which spent $34 billion on Red Hat, or SAP, which spent $8 billion on its acquisition of Qualtrics, Apple hasn't historically bet the farm on big deals.

Some of Apple's big acquisitions in the past include its $400 million purchase of Shazam in 2017 and its $3 billion acquisition of Beats in 2014, but mergers and acquisitions of that scope are few and far between.

Do you know which 20 to 25 companies Apple acquired in the past six months? We want to know more. Contact the author at bpeterson@businessinsider.com or DM her on Twitter if you have more information about Apple's M&A habits.