The bad news for American Express just won't stop

The hits keep on coming for American Express.

On Thursday, a report from Bloomberg News said that American Express violated antitrust laws by barring businesses from asking customers to use lower-cost credit cards.

Following this report, shares of the credit card company were down about 1.8%.

This latest bit of negative news for AmEx follows a tough week in which the company saw its partnership with Costco end, while a report from Bloomberg said that airline JetBlue was also ending its co-branded card agreement with the company.

In a note to clients last week following the Costco news, Oppenheimer analysts said, bluntly, that “everything is moving in the wrong direction” for American Express.

Oppenheimer estimated that the Costco relationship represented 20% of AmEx’s worldwide loans, 8% of billed business, and 10% of the AmEx cards outstanding.

Since the beginning of last week, shares of AmEx are down about 8% and this year, the company’s stock is down 15%.

In its note last week, Oppenheimer said:

Bottom line: American Express is a fantastic company in our view, and we have no doubt that it will work its way through these headwinds over time. With that said … it will be difficult for the stock to outperform with the fundamentals under pressure for the next 12-18 months.

As of Thursday, American Express still seems to be under pressure.

NOW WATCH: Nationwide’s Super Bowl commercial about dead children is about corporate profits … in a way that we can all appreciate

NOW WATCH: Money & Markets videos

Business Insider Emails & Alerts

Site highlights each day to your inbox.

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.