Carbonite Inc. which sells itself as a safe backup for a customer’s important computer files, faces a proposed class action led by a California law firm that lost vital data when the backup system suffered a serious glitch.

Shainfeld & Anvar which advertises itself as a boutique “consumer law” firm dedicated to “helping protect the rights of people who are wronged,” wants to do just that for others of Carbonite’s 1.5 million customers who it says might have fallen victim to a similar data disaster.

The Santa Monica firm on June 4 filed complaint in U.S. District Court for the Central District of California that alleges the data backup firm violated California consumer-protection and business laws, and engaged in unjust enrichment, false advertising, fraudulent concealment and breach of contract.

The law firm says it is particularly angry that Boston-based Carbonite didn’t alert it quickly that its supposedly backed-up data in Carbonite’s system had been corrupted on April 10.

Instead, Shainfeld & Anvar learned those files were kaput on April 28, when it tried to access its in-house computer network only to find a hardware problem rendered it inoperable, according to the complaint. The law firm contacted Carbonite to secure the duplicate versions, only to be informed that, those files could neither be retrieved nor restored, due to the glitch.

The complaint, Shainfeld & Anvar v. Carbonite, says the law firm paid $800 for Carbonite’s services and seeks restitution, damages, injunctive relief and attorneys’ fees and costs.

The plaintiffs’ attorneys are Todd Friedman and Nicholas Bontrager of the Law Offices of Todd Friedman.

Lisa Hoffman contributes to