Innocent mistake or bold scam?

I received a letter with the following envelope information:

FROM:
MFS MUTUAL FUND SETTLEMENT
In re Mutual Funds Investment Litigation
c/o The Garden City Group, Inc.
P.O. Box 9410
Dublin, OH 43017-4510

TO:
MFS HERITAGE TRUST CO TRUSTEE
IRA A/C RICHARD R DUFFIELD
(my street address here)
(my city, state, and zip here)

The letter is not addressed to me so I did not open it.  But  I am the first home owner at my address and the house was built to my specifications a few years ago.  So I know that a Richard Duffield could never have had this address.

It could have been a mistake in the address, but I suspect it's an attempt at fraud by pretending an administrative mistake and  luring someone into paying fees to receive someone else's settlement. Once the victim takes the bait the scammer can also blackmail them because technically the victim also committed a crime by opening mail addressed to someone else.

I didn't open the envelope. I marked it "not at this address" and put it back in my mailbox for the postman to pick up. I think that's the right thing to do when receiving mail addressed to someone else who I don't know.

Settlements

Someone (DoofusOfDeath) on Slashdot posted his opinion on settlements, in reaction to the settlement that Dell reached with the SEC regarding Dell cheating on their financial statements. I think I agree with him:

1. settlements are shakedowns, not justice.  Maybe the government thinks you're guilty but isn't sure it can prove it, or you know you're guilty and don't want a conviction, or you're innocent but settlement costs less than a full defense, or - the worst - the government knows you're innocent but is hoping you'll go for settlement instead of a full defense.

2. wealthy people can buy their way out of criminal convictions, whereas the poor cannot. that is unjust.

3. settlements allow corporations to protect its employees from responsibility for their actions; of course that's the purpose of a corporation but settlements allow the business to continue as usual, whereas a conviction would allow a higher penalty and possibly the end of that corporation's right to exist which means the punishment to the employees would be the loss of benefits and possibly loss of a job.