If you’re involuntarily bumped from an overbooked flight, or if your bags are lost, the airline owes you some form of compensation. It turns out that four carriers — American, United, Alaska, and Southwest Airlines — haven’t exactly been forthright with all their passengers when it comes to getting what they are owed.

The Department of Transportation recently announced that it would fine each of these airlines between $35,000 to $45,000 for failing failing to give passengers accurate information about how much compensation they should get for being kicked off an overbooked flight or for lost and damaged luggage following a series of inspections.

In all, American Airlines was fined $45,000, Southwest Airlines and Alaska Airlines were fined $40,000 each, and United Airlines was fined $35,000.

Under DOT rules, passengers are eligible for compensation when they are involuntarily bumped from an oversold flight. However, the amount of compensation is based on several factors including the planned arrival time of the substitute transportation arranged or offered to be arranged.

Per the rules, the airlines must immediately provide affected passengers with a written statement explaining the terms, conditions, and limitations of denied boarding compensation, and describing the carriers’ boarding priority rules and criteria.

According to the DOT’s consent orders with the airlines, it found each failed to provide passengers with required information in a timely manner.

For Alaska Airlines, the DOT found [PDF] in multiple instances that agents produced outdated copies of the denied boarding statement, with compensation amounts below the minimum value required. IN some cases, the amount offered was more than five years outdated.

The consent order [PDF] for Southwest Airlines, details issues in which agents failed to produce proper copies of Southwest’s written denied boarding statement in response to specific requests by DOT staff.

“Specifically, a Southwest agent at SAT was not able to produce a copy of the denied boarding statement at the ticket counter,” the order notes. “Another Southwest agent at OAK provided only a partial copy of Southwest’s denied boarding statement, and that statement contained compensation amounts $25 to $50 below the actual amounts.”

The order [PDF] for United Airlines claims that agents at boarding and ticketing locations for the carrier failed to produce proper copies of United’s written denied boarding statement in response to specific requests.

In some cases, the agents couldn’t produce any copies of the statement, while other only had outdated copies on hand.

Likewise, the DOT claims [PDF] in it order for American Airlines, that the carrier’s agents could not how staff copies of its written denied boarding statement.

During compliance inspections, the carrier was found to display incorrect domestic baggage liability limit notices. Per the DOT rules, the top payout carriers must pay passengers whose luggage has been lost or stolen is $3,500.

In American’s case, the displayed liability amounts were sometimes more than seven years outdated.

Each of the airlines are required to update their policies and provide passengers with accurate information related to compensation.

“We are committed to ensuring that air travelers know the rules and have accurate information about compensation when they are bumped from flights and for lost, damaged, or delayed baggage,” Transportation Secretary Anthony Foxx said in a statement.

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