why do you say that's the corner of the tint? The tint guy used a knife and couldn't get through and had to use alot of force to get through it. The scratches all feel like grooves so we believe it is reflective treated / coated glass.

Do you think we can get this out with a polisher like what glass repair guys use?

That black line is the glazing compound from the outside i think?

The logo in the picture applies only to the tempered glass, and nothing else. It doesn't indicate who made the IG unit or who made the window itself (likely the same company, I suspect). Is there any other identifying information on the glass?

Per the logo the tempered glass meets the 1978 safety glazing standard which doesn't mean that the glass was made in 1978, but the next update to the standard (as I recall) was 1984, so its likely, but not certain, that the glass was made in late 70's or early 80's. I bring that up because if it is a glass coating versus after-market film it probably hasn't been made in a long time - meaning it might be difficult to find someone who is familiar with it.

Like WoW I also think that looks like an aftermarket film as well based on the pictures, and if it has been on there a really long time it could be next to impossible to remove unfortunately.

I also agree with WoW that you ask the building manager or maintenance staff to see if they have any additional information on what you have there

If it is an actual window coating, rather than a film, then I would say that there is nothing reasonable that you can do to remove it and if you want it gone glass replacement might be the only option.

Apartment built in 1984 - this is original glass that hasn't been changed. Apartment was renovated twice but windows never touched. This is an apartment in Hong Kong so the windows are all custom and its tempered for typhoon protection.

Someone said if you polish the glass, the coating will come off?

I had a tint guy come to try to scrape it who assured me it wasn't tint but my suspicion is that there's glass from 3 different manufacturers but the tint is the same - so i suspect it must be film unless they all coated it the same way? Maybe its just stubborn old tint. How do I check to see if its tint or not as a first step? Use steamer?

Can't remove glass since its a high floor apartment and requires scaffolding

I am not aware of any polishing options to remove what was originally an applied film. That said, I am not a tint specialist. Oberon, however, is a glass specialist and I would defer to his expertise in this matter. It is very likely that what you have here is a very old applied film (per my previously edited picture) that has, in effect, fused itself to the glass.

You might have some luck if you introduced a bit of heat via hairdryer or heat gun (be sure to not damage the IGU here) to soften the film in preparation for removal.

I am not aware of any reasonable way to remove an applied coating.

If it is an aftermarket film then I would agree with WoW that it might have fused with the glass to the extent that you can't get it off to any level of acceptability.

Best bet with aftermarket film would be to apply heat and see what happens if you scrape it..

I had aftermarket tinted windows, upper and lower that covered one long wall. The trick was using a hand held hair dryer. Get one corner of the film loose, then direct heated air up toward the underside of the film, while the film is being pulled up. Easily removed film that was applied 35 years ago on all 8 large windows by myself.

Not creepy at all. Nope.