NEW DELHI: India, which accounts for over 93 million Facebook users, reported the largest number of bugs under the social networking giant’s bug bounty program last year.

The California-headquartered firm said it received a total of 14,763 submissions in 2013, of which 687 bugs were found to be valid and eligible to receive rewards.

A bug is an error or defect in a software or hardware that causes a program to malfunction. It often occurs due to conflicts in software when applications try to run in tandem.

The social networking platform, which has over 1.2 billion users globally, paid $ 1.5 million last year to security researchers who report bugs on its website.

“India contributed the largest number of valid bugs at 136, with an average reward of $ 1,353. The U.S.  reported 92 issues and averaged $ 2,272 in rewards,” Facebook said in a post.

Brazil and the U.K. were third and fourth by volume, with 53 bugs and 40 bugs and average rewards of $ 3,792 and $ 2,950, respectively, it added.

Researchers in Russia earned the highest amount per report in 2013, receiving an average of $ 3,961 for 38 bugs, Facebook said.

It said: “We’ve paid over $ 2 million since we got started in 2011, and in 2013 we paid out $ 1.5 million to 330 researchers across the globe.”

The average reward in 2013 was $ 2,204, and most bugs were discovered in non-core properties, such as websites operated by companies the firm had acquired, it added.

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