Thought this may be appropriate as it is news for me... (from the T&C's)
Up to 5X StarpointsŪ on Eligible Purchases
StarpointsŪ are awarded by American Express as part of the Card's reward program and by Starwood through the Starwood Preferred GuestŪ Program. Because the program terms differ, there may be instances where you receive Starpoints under one program but not the other.
Starpoints awarded by American Express. You will receive two StarpointsŪ from American Express for each US dollar of eligible purchases charged on your Starwood Preferred Guest Credit Card from American Express when charged directly with participating Starwood properties, standalone Starwood retail establishments, and Starwood online stores that, in each case, are wholly owned by Starwood Hotels & Resorts Worldwide, LLC (a subsidiary of Marriott International, Inc.) and its affiliates. You will also receive two Starpoints from American Express for each US dollar of eligible purchases charged on your Starwood Preferred Guest Credit Card from American Express when charged directly with hotels participating in Marriott RewardsŪ, standalone Marriott branded retail establishments, and Marriott branded online stores (including online purchases of Marriott branded gift cards), that in each case, are owned by Marriott International, Inc. and its affiliates.
Starpoints awarded by Starwood. Independent of using the Card, you will receive two Starpoints (or three Starpoints if you have Starwood Preferred GuestŪ Elite status) from Starwood for each US dollar of eligible charges under the Starwood Preferred Guest Program for stays at participating Starwood properties, standalone Starwood retail establishments, and Starwood online stores that, in each case, are wholly owned by Starwood Hotels & Resorts Worldwide, LLC (a subsidiary of Marriott International, Inc.) and its affiliates. Starwood associates do not receive any additional Starpoints as a Starwood Preferred Guest member for hotel stays and purchases. For information about receiving Starpoints through the Starwood Preferred Guest Program, please see the SPG Terms and Conditions at spg.com/terms.
Year-End Summary
The Online Year-End Summary, available each January, reflects charges posted to your account from January 1st through December 31st of the prior year.