# MIP-19: Reserve Balance-Compatible SETCODEFROM Opcode

**URL:** <https://forum.monad.xyz/t/mip-19-reserve-balance-compatible-setcodefrom-opcode/572>\
**Category:** MIPs\
**Created:** [October 29, 2026, 8:07am UTC](https://forum.monad.xyz/t/mip-19-reserve-balance-compatible-setcodefrom-opcode/572 "2026-10-29T08:07:44Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![mav3rick](https://avatars.discourse-cdn.com/v4/letter/m/53a042/32.png) [@mav3rick](https://forum.monad.xyz/u/mav3rick)\
**Post date:** [October 29, 2026, 2:51pm UTC](https://forum.monad.xyz/t/mip-19-reserve-balance-compatible-setcodefrom-opcode/572/4 "2026-10-29T14:51:38Z")

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Thanks, both points taken. On the compromised key you are right: our data is about keys leaked long before migration, which is not the case the section covers.

On accounts that are not delegated today, here is a first number. Over the last 3,000 mainnet blocks (to 117,639,095, about 20 minutes) there were 822 distinct senders: 94.2 % plain EOAs with no code, 5.8 % delegated, none with contract code. Of the plain EOAs, 500 of 774 hold at least 0.1 MON, enough to send the single type-4 transaction that delegates and adopts. So the active accounts mostly can take the self-sent path; the 80 % of delegated accounts without MON are the sponsored ones that never send their own transactions.

A 20-minute window leans towards bots; I can run it over a day or a week if that helps.

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