By Sam Oliver

Published: 12:50 PM EST

Apple is not idly standing by as patent holder Lodsys has sent legal threats to members of its iOS development community, according to a new report.

Apple is not expected to respond to the claims until later this week, according to The Guardian. It also revealed that about a dozen total iOS developers have been issued the legal threats from Lodsys.

According to the report, Apple's legal department is "actively investigating" the claims made by Lodsys. The patent owner seeks payment from developers that utilize Apple's in-app payment systems for transactions in iPhone, iPad and iPod touch software available on the App Store.

Lodsys spoke out on the issue this weekend with a series of posts on the company's official website. It revealed that Apple is licensed to offer in-app purchases, but argued that developers must also pay for the right to use Apple's service.

Though no official legal action has been taken, developers began receiving letters from Lodsys last week, accusing them of patent infringement. Those developers were given 21 days to license the technology related to in-app purchases.

Lodsys seeks 0.575 percent of U.S. revenue covering the period of the notice letter to the expiration of the patent, plus applicable usage. The company noted that would amount to $5,750 per year for an application that makes $1 million in annual sales.

The threats are based on U.S. Patent No. 7222078, entitled "Methods and Systems for Gathering Information from Units of a Commodity Across a Network." The patent dates back through continuations to earlier applications as old as 1992 and is credited to Dan Abelow, but is now owned by Lodsys.

Developers are anxiously awaiting Apple's response, as it is the iPhone maker's iOS mobile operating system that includes the built-in tools for in-app purchases. The transaction method debuted in 2009 as part of iOS 3.0, and allows users to purchase additional content or software add-ons from within an iPhone or iPad application, without the need to exit and access the App Store.

Just like traditional App Store purchases, in-app purchases are charged by Apple to a user's iTunes account, connected with a credit card. Apple takes a 30 percent cut of all transactions made through the App Store or via in-app purchases.