Apparently there is a 3X MR for Amazon out there
Found on all of my membership reward cards
ENROLLMENT/ELIGIBLE CARDS: By enrolling and making an eligible purchase, you consent to American Express sharing with Amazon the fact that you redeemed this Amex Offer. Amazon’s use of this information will be subject to Amazon’s privacy policies and practices. Enrollment is limited. Enrollment opens on 7/17/2018 and continues until 8/28/2018. Must first add offer to Card and use the same Card to redeem. Only U.S.-issued American Express

Cards that are enrolled in the Membership Rewards

program at the time of purchase are eligible. Limit 1 enrolled Card per American Express Card online account. Offer is non-transferable. Your enrollment of an eligible American Express Card for this offer extends only to that Card. Your enrollment does not extend to any other Cards that may be linked to your Card account (such as Additional Cards). ELIGIBLE PURCHASES: Offer valid only for purchases made at Amazon .com and via the US Amazon mobile app using your enrolled American Express Card after enrollment and prior to 8/28/2018. Excludes corporate gift card and custom-designed gift card purchases. Not valid at international sites owned and/or operated by Amazon or websites affiliated with/linked to/from Amazon .com. To the extent Membership Rewards points are used toward purchases, such purchases do not qualify for this offer. Offer not valid for Amazon Local, Amazon Mechanical Turk, Amazon Web Services, Amazon Home & Business Services, Amazon Currency Converter, Home Services, Prime Photos, Amazon Inspire, Amazon Video Direct, Amazon business, Amazon Global, or Amazon Drive. See Amazon .com for shipping policy. Amazon may not ship to all areas. If American Express does not receive information that identifies your transaction as qualifying for the offer, you will not receive the additional points. In addition, in most cases, you may not receive the additional Membership Rewards points if your transaction is made with an electronic wallet or through a third party. EARNING POINTS: You will receive 2 additional Membership Rewards point(s) per dollar spent using your enrolled American Express Card in accordance with the terms of this offer. These additional points are in addition to any points you would normally receive for purchases on your Card under the terms of the Membership Rewards program. When we calculate the additional points benefit for Amex EveryDay

Card products, points awarded under this offer will not be included. Additional points will be credited to your Membership Rewards program account within 90 days after 8/28/2018, provided that American Express receives information from the merchant about your qualifying purchase. We may not credit additional points to, or we may take away additional points that have been credited to, your program account if the qualifying purchase is returned/cancelled. Terms and conditions for the Membership Rewards program apply. Visit membershiprewards.com/terms for more information. Participating partners and available rewards are subject to change without notice. The value of Membership Rewards points varies according to how you choose to use them. To learn more, go to
www.membershiprewards.com/pointsinfo. By adding an offer to a Card, you agree that American Express may send you communications about the offer