Declaration (宣言, Sengen) is the fifth chapter of volume twelve and the one-hundred-third chapter of the Death Note manga series.
Plot
At the last second, Light declares, "I win, Near." Everybody braces themselves. 40 seconds pass and nobody dies, exactly as Near predicted.
Mikami begins to panic. He faces Light and cries 'G-God... I-I did as you told me'. Near orders Anthony Rester and Stephen Gevanni to detain Mikami and bring him the notebook. Near opens the notebook and shows the Task Force the names on the page, noting that Light's name is conspicuously missing. Near concludes that the missing name, in addition to Mikami calling Light 'God', indicate that Light is Kira.
Light panics and screams that Near is trying to frame him and that the lack of deaths by Mikami's notebook means that Near trapped him. The Task Force looks on in shock at Light's breakdown and non-sensical argument. Near tells Light, as he said before, that nobody died because he replaced the pages. Light stutters and repeats that this is a set-up. He claims that he doesn't know Mikami.
Matsuda collapses on the floor in sadness. Aizawa tells Light to give it up and that his declaration of victory was effectively a confession. Aizawa restrains Light as Mogi brings over handcuffs. Light knocks the handcuffs out of Mogi's hand and runs away, resting on the wall of the Warehouse.
Near tells Light that he has lost. Near tells Light that he knew of his plan for Mikami to carry around a fake notebook and use it in front of Gevanni, baiting Near into replacing the pages of the fake notebook rather than the real one. Near reveals that he knew of the real notebook too and tampered with both. Near produces the real notebook from beneath his shirt.
Near explains that, on the previous night, Gevanni and Rester copied Mikami's handwriting and used the exact model of pen Mikami used, to create an entire fake notebook. This meant that Mikami had been using two fake notebooks unwittingly. Near reveals that, due to the fact that he had already made contact with the notebook, he had been able to see Light's Shinigami the whole time. He introduces himself to the Shinigami, who chuckles, and gives his name as Ryuk. Near asks Ryuk whether pages that had been cut out of the notebook would still function as normal. Ryuk confirms this is the case. Near wonders how many people Light murdered using this tactic.
Near, once again, declares that Light is Kira. Light wonders to himself how Near could possibly have executed this plan. He theorises that Mikami may have betrayed him, but quickly dismisses this theory, believing that Mikami would rather die than betray his God. Near tells Light that he is wrong and he owes his victory to Mello.
Conception
Tsugumi Ohba said that the chapter title "Declaration" was given because of when Light declares victory leading Near to declare that Light is Kira. Ohba added that Near's statement, "I owe this to Mello," could also be a declaration.