The TV series is directly copying heraldry designs from the wiki

[The Dragon Demands]

As I explain here:

http://gameofthrones.wikia.com/wiki/Oathbreaker#A_note_on_heraldry

I had my suspicions when the House Stokeworth sigil which appeared as embroidery in Season 5 bore an uncanny resemblance to the one used on AWOIAF.

...now, the House Reed sigil which appears as a stylized coat clasp in Season 6, upon close inspection, is a DIRECT copy of the specific design used on AWOIAF since 2012.  I mean, not only the circular shape, but even down to the tongue sticking out and bending at an angle to touch the tail. 

Is this theft?

Or flattery?

 

[House Mosse]

Nice one - good effort!

[DBD]

First off, let's start by assuming good faith? Throwing accusations around is not only not-that-nice but could also be libellous (worst case!) With my basic understanding of RW heraldry it's up to any particular artist how exactly to realise described arms, and sometimes there just aren't that many ways of realising something...

[The Dragon Demands]

...well I'm not really "accusing" -- I think that's why a lot of fanart gets made - in the hope that it gets "officially" used.  I just thought it was funny. 

[Alysanne Donnelly]

The description for the Reed's sigil is just "a black lizard-lion on grey-green." These two sigils  have an alligator, but they're both lying flat on their stomachs, so it's not a coincidence that the Reed sigil in the show is an exact copy of SiriusCrane's design.

SiriusCrane doesn't say if they got permission to use their original design, but they don't say much of anything else either. It's not my job to get angry for somebody else, but even if it turns out Sirius doesn't mind that they used the design without permission, this is still theft. If a person's original design is stolen by a multi-million dollar, award winning tv show; that's not flattery, that's being an uninspired dickhole.

If they loved it so much they wanted to use it, they could have paid the creator. Hopefully it doesn't go any further than the person making the buckle, but it could be the new costume designer who stole it. 

[Alysanne Donnelly]

The Stokeworth sigil is described as "a white lamb holding a golden goblet on a green field" which, again, is too vague for the extraordinary similarity between the sigils in the show and on the wiki to be a coincidence. Even the ones used before by the wiki are different. Yet the Stokeworth sigil embroidered by Michele Carragher has the lamb sitting in profile with one leg out to hold the goblet, just like the Stokeworth sigil by user Eagle of Seagard. Too bad they haven't been active in a year, they could tell us if anyone from GoT bothered to contact them.

Again, there's no way to know right now if it's one person on the production team or a "suggestion" by someone(s) in charge, but the fact is that book fans' original designs are being stolen for a series whose creators love to shit on them.

[The Dragon Demands]

Happened again in the Season 6 Histories & Lore sets.  The Harlaw and Drumm heraldry is a direct match to AWOIAF (scythe and skeleton hand), and Hightower is awfully similar.

Moreover...they're also copying Game of Thrones Wiki, for the TV series.  You see about a year ago a new illustrator fan came on and after much deliberation we changed the shape of the shield icons we use, right?  So instead of a perfect semicircle, they're pointed at the bottom - sort of like what's in the on-screen "Book of Brothers".   In the "Riverrun" video, the Frey heraldry which appears above their hearth is an *exact* match to the new shape we use, not a normal shield shape.  Not as bad in that case because they originated the Frey design, all we did was make the border shape.

...really, most "major" heraldry has appeared in the TV show by this point (well, if you include the animated featurettes).  Only one we kind of need still are Velaryon....but damn it, they showed it in a stylized manuscript in the Dance of the Dragons featurette.  I'll figure something out.