Toys R Us is preparing to close all of its US stores as part of a liquidation.

The toy chain's gift cards and loyalty-based "rewards dollars" and "endless earnings" will expire in 30 days, the company told Business Insider.

Blowout clearance sales at its 735 US stores could begin within weeks, according to Corali Lopez-Castro, a bankruptcy lawyer and managing partner at Kozyak Tropin and Throckmorton.

Toys R Us said in a bankruptcy filing Thursday that it must liquidate, meaning it will sell or close all of its US stores.

That means blowout liquidation sales at its 735 US stores could begin within weeks, according to Corali Lopez-Castro, a bankruptcy lawyer and managing partner at Kozyak Tropin and Throckmorton.

Toys R Us has already set a an expiration date of 30 days for its gift cards and loyalty-based "rewards dollars" and "endless earnings," the company told Business Insider.

"Toys R Us is not going to want to drag this out," Lopez-Castro said in an interview last week.

The longer the stores stay open, the more rent Toys R Us will owe to its landlords.

The company would need only a few weeks to heavily advertise the sales before starting them, she said.

Toys R Us filed for bankruptcy in September and recently started clearance sales at about 170 stores that it plans to permanently close in April.

The company has been shedding sales in large part because of growing competition from online retailers like Amazon.

"Brick-and-mortar stores are just getting bludgeoned to death by e-commerce," Lopez-Castro said. "I don't think people will miss Toys R Us," she added, "because everything you can get at Toys R Us, you can get online."

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