Veeam has claimed victory over Symantec as the latter's lawsuit over backup patents unravels.
Symantec had started legal action against its backup rival in 2012, claiming Veeam infringed four separate patents.
"Veeam unlawfully leverage[s] Symantec patented technologies in their respective backup and replication products," Symantec said in a blog post at the time.
"This free riding on Symantec is wrong and Symantec has filed these lawsuits to protect its intellectual property."
However, Veeam has now argued its case successfully enough that Symantec has either been forced to dismiss its claims or had them declared invalid by the US Patent and Trademark Office (USPTO) over the last three years.
The latest blow to Symantec landed just last month, when it decided to cancel its appeal against the USPTO's decision to reject all its claims over the final patent.
Ratmir Timashev, CEO of Veeam, said: "This is a big victory for Veeam. I am pleased with the USPTO rulings. This case shows that Veeam will not back down in the face of threats, even when those threats are made by a large company like Symantec."
Symantec claimed back in 2012 that monetary compensation alone would not be enough to right the damage it claimed to have suffered, suggesting that one outcome if Symantec had won would be for some Veeam products to be banned from sale.
Last April, the USPTO determined that Veeam had established a reasonable likelihood of proving Symantec's claims were invalid.
The USPTO is expected to issue final decisions about the validity of the asserted patent claims in April 2015.
A Symantec spokesperson said: "The legal dispute between Symantec and Veeam remains ongoing and proceedings continue before the patent office and in federal court.
"Symantec continues to vigorously assert its legal rights to protect its intellectual property. As the legal dispute is still pending, we have no additional comment."
The news comes after Veeam announced 40 per cent annual growth compared with 2013 to hit $389 million revenue, claiming to be on course to reach its goal of $1 billion in annual revenue by 2018.
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