A U.S. court ruled on Thursday that Google did not infringe on Oracle's exclusive copyrights when the Internet giant implemented functions of 'application programming interfaces' or API on its Android mobile platform.

In a decision handed down Thursday by U.S. District Judge William Alsup in San Francisco, California, Google was freed from the hundreds of millions of dollars that Oracle claimed must be paid by the tech giant for using the API, a core function of Java that Oracle has acquired in 2009 when it purchased Sun Microsystems for more than $7 billion.

The court sided with Google's arguments that Android has been executing tasks via modified API codes, meaning the Android-maker took the liberty of utilising the basic Java codes with explicit modification in the whole design of the mobile platform that has been powering millions of mobile gadgets since its launch in 2007.

Judge Alsup has allowed on his ruling that phrases, which Oracle claims exclusive ownership of, were present on the popular Google OS, but he stressed too that existing copyright laws do not lend specific protection to short phrases, titles and names.

"So long as the specific code used to implement a method is different, anyone is free under the Copyright Act to write his or her own code to carry out exactly the same function or specification of any methods used in the Java API," the American judge was reported by Agence France Presse (AFP) as saying on his ruling.

Google's use of the Java API, Mr Alsup added, was crucial for Android to maintain its interoperability functions and there were no indications that the Oracle-owned codes were lifted with wanton disregard of a likely copyright dispute.

"Google and the public were and remain free to write their own implementations to carry out exactly the same functions of all methods in question, using exactly the same method specifications and names," The Associated Press quoted the U.S. court as saying in the decision.

The ruling somehow contradicted an earlier verdict handed down by the trial jury at the end of the suit hearing last week, which favoured Oracle when it deemed that Google lifted at least nine lines of codes that Oracle owns.

However, Mr Alsup said that his decision will not reverse the jury's findings, which at most, according to AP, will award Oracle payment claims of only $150,000 at the maximum for statutory damages.

As of press time, no official comment has been issued by Oracle on the matter but initial media reports said that the company is likely to launch an appeal soon.

For its part, Google said in a statement that the court ruling pointed to "a good day for collaboration and innovation."

"The court's decision upholds the principle that open and interoperable computer languages form an essential basis for software development," the tech titan was quoted by AFP as saying.