Written by Whitney Blair Wyckoff

The U.S. Patent and Trademark Office’s Web applications are back online Monday after a power outage took down its data center last week — causing filing, searching and payment systems used by examiners and the public to go dark.

“Our examiners are back at work and customers can once again search, file, and/or make payments,” the agency said in a blog post Monday afternoon.

IT staff worked through the Christmas holiday weekend to restore the systems, according to the USPTO. The agency said it plans to continue to make fixes over the next few days, which may cause systems to go offline again. It is maintaining a list on its blog of systems that could be offline.

In a statement released Thursday, the agency said the outage occurred Tuesday night after a malfunction in the power supply lines that feed into two power filtration systems.

“Because of their size, these large and highly complex power filtration systems cannot be easily replaced,” USPTO Acting Chief Communications Officer Patrick Ross said in the statement.

A USPTO spokesman would not say whether the outage was caused by malicious activity and whether this will change how the agency backs up its systems.

This summer, the Copyright Office, a separate intellectual property agency in the legislative branch, suffered a major IT outage when officials couldn’t bring a data center back online after routine maintenance. The nine-day outage ramped up calls to separate the Copyright Office’s IT from that of its parent agency, the Library of Congress, which managed the data center.

The Patent and Trademark Office promised in a blog post to “keep deadline flexibility in mind” as it continues to make fixes, and it already has given more time to users who faced deadlines (for example, a due date to respond to an office action) last week. But that hasn’t stopped people from taking social media to air their complaints about the outage.

“How can it take six days (and counting) to fix this?” European patent attorney Parminder Lally tweeted early Monday morning about the office’s Patent Application Information Retrieval system.

Meanwhile, Ryan Alley, a patent attorney in Northern Virginia, told FedScoop the outage forced him to snail mail a patent application in order to secure a Dec. 24 filing date. It required him to print hundreds of pages for the application while he was with family on Christmas Eve and then run to the post office to get the application postmarked.

“That was really inconvenient to my practice,” he said.

Editor’s note: The story has been updated with information from a Monday blog post.

Contact the reporter on this story via email at whitney.wyckoff@fedscoop.com, or follow her on Twitter @WhitneyWyckoff.