The crucial distinction is that the hypothetical passenger moving from their assigned seat to 12B would still be seeking to occupy one seat; if the OP vigorously attempted to prevent this passenger from sitting in 12B, she would be seeking to occupy two seats (while paying or having status for one).

Once the doors close, the reasonable expectation is for passengers to move to unoccupied, unblocked seats that they deem superior. (In their contracts of carriage, the airlines certainly view seats as fungible and refuse to obligate themselves to honor seat assignments.)

On an ERJ, 12B is a coveted seat, so the OP should not be surprised or overly upset if another passenger moves into it. Would it suck, yes; would it be unfair, no.

Whether to place personal items on the empty seat in an attempt to discourage a fellow passenger from sitting in it strikes me as a matter of personal ethics, and this thread reveals a spectrum of positions.

I once took a British Airways flight on a 747, as a super duper basic FF tier member. Unfortunately, I didn't get an upgrade, so I was stuck in economy class. I had a window seat and another passenger had the aisle seat. I prayed, while the FAs announced how full the flight was, that the person who was assigned to the middle seat would be a small person.

I was shocked to learn that the middle seat turned out to be the only empty one on the ENTIRE PLANE (the gate agent telephoned me and told me so) and that it had been blocked JUST FOR ME, because I'm a special super duper basic FF program member! Thank goodness for divine intervention which ensured the seat block.

FewMiles..

UA tries to block seats next to elites. It has always been my understanding that once the door is closed passengers can move to any open seat in their ticketed cabin, however. FAs frequently announce that passengers are free to change seats once the flight has fully boarded. FWIW, UA has written letters to customers explaining that the seat is not really "blocked," but they do try to keep it free when possible.

IMHO, this is a reason to make that "blocked" seat as unattractive to others as possible by moving things into it, putting tray table down, etc.

Very true! Was she an elite?

That's not quite correct. The OP would physically occupy only one seat while the seat next to her will remain empty throughout the flight.

This is under the assumption that the deemed superior seat is in the same class of service as the ticketed passenger. Although an exit row seat and a bulkhead seat are still technically Y seats, they are often reserved for elites and passengers who pay a premium for the added comfort. Now, is it really that inappropriate for these people to be rewarded for their loyalty/extra money?

LAX

OK, to be more precise, I construed the germane issue arising out of the OP’s original ethics query to be whether a passenger can prevent another passenger from sitting in an empty, adjacent seat. Your statement that “Since the seat is unassigned and unsold, thus no one on that plane technically has any right to that seat, including the OP” is seriously flawed. Passengers move to empty seats all the time, and absent crew instructions to the contrary, the seat being blocked for an elite, or another compelling reason, they’re justified in doing so. A considerate passenger should clear the move with a flight attendant, if possible, and should be exceedingly polite to any passenger who may feel peeved about the move.

In the ERJ scenario described in the original post, I would be interested in hearing how you would justify your position when informing another passenger that he or she cannot sit in the empty, exit-row aisle seat next to you.

We agree that airlines rightfully block seats next to their elites when feasible, which provides an exception to the “door is closed, move wherever you want” policy. Elites with an adjacent blocked seat have a compelling reason to turn away another passenger who tries to move into the seat. B747_437B describes another exception to the rule: when the airline blocks seats or rows for customer service reasons. These exceptions, however, do not undermine the general changing-seats policy evident on most airlines.

Agree with Arthurrs. What REALLY miffs me is when there is a light load and they still put the largest person on the plane right next to me. The kind of person where you can't even get the armrest down!

Under the same class of service principle...

If an elite is able to be assigned a (n exit row) seat when traveling under a deep discount fare (class of service), a non-elite traveling under the same fare is entitled to sit in such a seat that is unoccupied later in the flight.

Yes
 

I am elite with Continental. Since I have recently been flying almost exclusively on ERJ's, I don't get the opportunity to upgrade, unfortunately.

BTW, I didn't mean to hit a nerve with anyone. I was truly wondering if my tactics were appropriate or not. As I said, I don't "claim" the seat next to me until it is clear that the seat is unassigned, and I don't think I would have the nerve to turn someone down if they tried to take the seat. So far, what I've done is move the items UNDERNEATH the seat in front of me to UNDERNEATH the seat in front of the unoccupied seat and stretch my legs in a way that they are kind of between the seats to discourage anyone from trying to move there.

Analise, I read the linked thread about the woman who wanted you not to have a seat because she wanted her child to sit in your seat - I would never do anything like that, and I think you handled it beautifully.

Not exactly what I meant
 

I have not and cannot imagine actually denying someone who tried to sit in the seat. I was discussing tactics to discourage another passenger from taking the seat (kind of like the poster on this thread that said he tried to "look big" to discourage anyone from taking an unoccupied seat next to him).

Also, I mentioned that I try to check-in at the first available time for the flight (24 hours ahead of time, for Continental) to ensure that I get my preferred seat. If 12B is unoccupied at the time that other passengers check in, I would assume that they could choose that seat at that time, but, in the cases I'm discussing, they didn't.

Now, there could be a few reasons for this. First, as a few people have pointed out, perhaps the seat was blocked for me because I'm elite (I have no idea whether this is the case). Second, the person could have not known to ask for the exit row on this airplane (not realizing how little leg room there is in non-exit row seats). Third, the person could normally be fine with the regular seats, but gets seated next to a COS, and needs to move to breathe (I'm tall and could stand to lose some weight, but I fit well between the armrests).

As I said, I can't imagine turning someone down if he or she tried to move to the seat, I just want to subtlely discourage it. If someone wants the seat bad enough, he or she will move anyway.

I've read elsewhere on FT that wearing a surgical mask (and perhaps coughing regularly) helps keep the seat next to you free :p

Exactly. But there's no harm in trying. "Seat blocking" strategems do not work on me either in busses, or when I have an "inferior" airline seat at door close, and the "musical chairs" begins.

Sometimes I have fun with it. I was on a 747 in coach (3-4-3) on an inside aisle, when a group of ebullient German-speaking soccer players took the three seats to my right, and some in the center rows fore and aft. Because they were all conversing loudly (and perhaps a little drunkenly), they did not seem inclined to move.

The three-seat window row to my left was empty. Behind that row was a family consisting of parents and a mid-teenage boy. He saw me eyeing the empty row, and beat me to the punch, grabbing the window seat (perhaps even before the door was closed). Check. As soon as the door did close, I moved into the middle seat next to him, with a friendly, "It's always nice to be able to see out of the window, isn't it?" Mate. He almost immediately moved somewhere further aft, and I had the whole row to myself.

Sometimes seat blocking tactics are de rigeur. Take a London-Edinburgh train out of London in the evening, and everyone does it.. bags on seat next to you in the hope of getting double seat to self. In fact the latest fad, which I won't do, is to take the aisle seat and put stuff in the window because the train has to be very full before people will insist on claiming that seat. However, if you are caught, you are caught - being asked "is that seat taken?" means you have to give in and move your stuff. Regular travellers know the unofficial rules of travel ;) So i dont really see a big issue with what the OP is doing, as long as she moves them if someone asks or wants to sit there, and she has already said she will.

Thanks. :) I knew your question had nothing to do with that situation last weekend. If I came across too strong, I do apologize. I was still raw from the whole thing.

This is exactly my issue/question. Several times now I have observed the following:

Somebody (me or other) is settled down comfortably in exit row window. Somebody else in aisle. Both people have status, so both assume that since the flight is maybe 40% full, that seat will stay empty between them. Door closes and somebody comes scurrying up from the back of the plane and wedges in between the other two, into the middle exit row seat.

To me, that seems unfortunate at best, and unfair at worst. For all the reasons previously mentioned, if somebody wanted the seat they could have asked for it beforehand, at the gate, the FA, or even asked permission of the two people who are being inconvenienced. But in most of these cases the guy (never had a woman do this) doesn't even ask permission. He might say excuse me to get by, but that's it.

I don't think that person is entitled to the seat. Am I wrong? Maybe I should say something when this happens to me, and just be a ----- about it, instead of quietly steaming for a few minutes (or longer if he's gigantic and elbowing me in the ribs the whole way while kicking off his shoes and revealing bare feet :mad: ) but being essentially non-confrontational.