Bloomberg has made public its valuable application programming interface (API) for market data, making it free for trading firms and software developers to access the code.

The API works with a number of programming languages and operating systems, including Java, C, C++, .Net, COM and Perl, and is designed to be "simple" as well as suitable for low latency applications, Bloomberg said. It is available here.

The move to make the interface public contrasts with Bloomberg's past practice – and that of arch rival Thomson Reuters – of making firms pay for using a particular set of systems to access the data. The move is part of Bloomberg's Open Market Data Initiative.

Thomson Reuters is currently embroiled in a dispute with EU antitrust officials over its own APIs. The officials allege the company is taking advantage of its dominant market position by restricting access to the codes.

Bloomberg's API is available to companies that are not customers, allowing them "an alternative" to proprietary technology, the data firm said. It intends for the initiative to "spur innovation" in the financial services industry. Around 100,000 financial services staff use the Bloomberg API daily.

"We intend to evolve BLPAPI into an open standard with the help of an independent committee charged with managing the future development and stability of a truly open market data interface," said Shawn Edwards, chief technology officer at Bloomberg.

Bloomberg also recently released its Open Symbology API, a system used to identify securities across all global asset classes.