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American Express and Air France-KLM are partnering to offer targeted cardholders a couple of great Amex Offers. With each of the two separate Amex Offers, you can get 20,000 Membership Rewards points for spending $1,000 or more with Air France or KLM.
Some members of the TPG team were targeted for only one of the offers on an account, while others were targeted for both Air France and KLM. For both offers, if you were targeted, you must add it to your card and spend a minimum of $1,000 in one or more eligible transactions directly with the respective carrier. According to the terms and conditions, you must make the purchase through the US version of the airline website.
Here’s the KLM offer:
… And the Air France offer: 
Based on TPG’s most recent valuations, which peg Membership Rewards points at 1.9 cents apiece, the 20,000 Membership Rewards points are worth $380. If you’re targeted for both of the promotions, enroll and successfully meet the spending requirements, you’ll walk away with 40,000 bonus Membership Rewards points, worth $760 — a great return on your purchase. Plus, you’ll earn bonus points per dollar spent on the airfare — 5x if you book with the Platinum Card from American Express.
Keep in mind that both of these particular offers expire on July 31, 2018.
Source: thepointsguy.com