The purchases added to the 1 000 or so patents the internet firm bought from IBM in July and reportedly ranged from mobile software to computer hardware and processes.
Google spokesperson Jim Prosser said that the patent transfers had taken place, but would not disclose financial terms of the deal or specifics regarding the intellectual property.
The push by Google to strengthen its patent portfolio comes as the fight for dominance in the booming smartphone market increasingly involves lawsuits claiming infringement of patented technology.
Smartphone titan HTC this month ramped up its patent war with Apple with the help of ammunition provided by Google, the force behind Android mobile software.
Google transferred a set of patents to HTC that the Taiwan-based company used to amend intellectual property infringement complaints against iPhone maker Apple in the US.
In August, HTC accused Apple of patent infringement as part of an ongoing legal battle.
In a lawsuit filed in US District Court in the state of Delaware, the Taiwanese smartphone maker charged that Apple violated three HTC-held patents in its Macintosh computers, iPods, iPhones, iPads and other products.
HTC also filed a complaint with the Washington-based US International Trade Commission.
Technology giants have taken to routinely pounding one another with patent lawsuits. Apple has accused HTC and other smartphone makers using Google's Android mobile operating system of infringing on Apple-held patents.
Some of the nine patents that HTC got from Google had belonged to Motorola Mobility, which Google is buying for $12.5bn in cash.
Motorola Mobility's trove of patents was a key motivation for Google, which is keen to defend Android.
"Our acquisition of Motorola will increase competition by strengthening Google's patent portfolio, which will enable us to better protect Android from anti-competitive threats from Microsoft, Apple and other companies," Google chief executive Larry Page said when the Motorola Mobility buy was announced.
Motorola Mobility chief executive Sanjay Jha told financial analysts the US maker of smartphones and touch screen tablet computers has over 17 000 issued patents and another 7 500 pending.