Seal of the people ?

[fuatX]

i got seal of the people from the tower at linang city
duke qi offers his sister as wife, yan princess cutting my way and demanding the seal, wtf is the secret behind of this seal? what if i dont give ? what will happen? really curious about this

[thekhanlives]

3 seals are all pieces of one seal... used to get a certain ending. If you do give it to duke kang to marry his sister, you can trade him to get it back

[darkshintos]

If you don't give it to Duke Kang, you don't get to marry his sister. Duh.
Same deal with the other 2 seals if you want to bond with Rurui.
Nothing else happens if you do or don't give it to him.
You can trade them back from him (or steal them) if you can still interact with him.
The only person who gives them back to you as a part of their quest is Sakuraha/ Liu Yueying .
Giving the Seal to Wanyan Zhaoning doesn't do anything. You will have to recruit her or kill her to get it back later.
Other people getting the seals don't do anything, not even if you trade them all 3.

You can get the secret of the 3 seals in a few ways (Which also unlocks the recipe to combine them). The easiest being given to you for free once you find the Seal of the State at the Back of the Jiuli Tribe .
Other methods include interacting with one of the groups after the 3 seals (Like the Sea Serpent Gang)

You want all 3 because they combine to become the best accessory in the game, you get the effects of all 3 Seals at once.
Story wise: The Imperial Seal (Combination of all 3 Seals) is what gives you the right to become the Emperor at the end of the last Duke Chai fight. You need it because you don't have royal blood unlike the other 3 Dukes. It was split into 3 Seals when the Emperor was captured. The 3 captors split it up so no one of them could take over the country right away (Because they all want chaos in the land for their own purposes).
Other forces (Great Ant City) are searching for it so they can negotiate a place for themselves in the country despite being foreigners.

[INFIN8]

you can do quest pink girl first as it required seal of people, don't worry you gonna get back the item again. or you can trade to duke to get the seal again.

[fuatX]

thnx

[renanqi001]

Since others explained the matter quite eloquently, I'll just add that it would be a good read for you if you look up the story behind the imperial seal of China. In reality, the seal was never split into three, mind, but it does give you an idea of why all those people and groups want it so badly.

Religious institutions were never superior to royal power in China, so we had a concept of 'mandate' (again, another good read if you're interested). The old emperor being captured by 'barbarians', King Qi(actually it is equivalent to a European duke, common mistake in translation) bowing down to said 'barbarians', King Kang being a plotting insensitive asswipe can all be interpreted as 'losing the mandate'. To be fair, natural disasters such as floods, earthquakes or droughts were also seen by the masses as 'losing the mandate', but people were awfully superstitious back then.

However, in the end, what matters is still who has the biggest fist, thus for the emperor ending, you NEED to finish Ye army quest line, and have a seasoned veteran army which saw YOU actually fought back against the invaders, while the old rulers prosecuted their old leader out of sheer politicking. (He is based on the real life national hero, Yue Fei, and again, another wonderful read. Strongly recommended.)

Sorry for rambling on if you're not interested, but I assume that since you bought this game and was interested in the lore behind the seal, you might be interested by the stuff I mentioned above as well.