Via One Mile at a Time, Starwood has changed the rules for transferring Starwood points between accounts.

Starwood Lets You Share and Combine Points, So You’ll Have Enough Points for Award Nights at Hotels Like the Westin Grand Cayman. But the Rules Have Changed!
Here’s what has changed. And how the new rules might affect you!
New Starwood Points Transfer Rules
If you’re transferring Starwood points between accounts, you must now do so in increments of 1,000 Starwood points.
And each account can only have 30,000 Starwood points added to it from purchases per calendar year. This includes points added from transfers between accounts.
What Does This Mean for You?
Starwood lets you transfer points between accounts for free, as long as both the parties share the same household address. The last names do NOT have to match, but the addresses do! And the addresses have to be the same for the last 30 days.
In the past, there was no minimum or maximum amount of points you could transfer.
But now you must transfer Starwood points in 1,000 point increments.
This isn’t a huge deal, except that you’ll probably have a few leftover Starwood points in your account after making a transfer. Because you likely don’t have exactly 1,000 Starwood points or more in your account!
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