Equity tiers and rate limits are put in place to prevent spam on the orderbook and prevent the blockchain state from getting too large which can potentially impact performance. For the latest numbers on rate limits, check the dYdX V4 docs here

Equity tier limit defines the set of equity tiers to limit how many open orders a subaccount is allowed to have.

For example with 20 USDC in equity value, a trader can have 1 open order, with 100 USDC, they can have 5 open orders and so on, according to this link: Other Limits · dYdX · v4

Each isolated position is individually subject to equity tier limits. Therefore, to open an isolated position via a long-term order, there must be at least $20 USDC of margin backing the position. If the isolated position has <$20 of margin backing it, its long term/conditional orders will fail.

Head here to learn more about using Isolated Margin.

The block rate limit defines the maximum number of CLOB specific operations per block. For example, with short-term orders a trader can place 200 order attempts per block, for stateful orders the limit is 2 per block or 20 per 100 blocks.
For more you can refer to the below link:
​Other Limits · dYdX · v4

All rate limits are subject to change. The latest limits can be queried via the https://<REST_NODE_ENDPOINT>/dydxprotocol/clob/block_rate endpoint, or via the docs here.

Note that rate limits are applied per account. That is, subaccounts under the same account share the same rate limit.

The equity tiers and block rate limits were initially defined in the genesis file of the v4 open source software (”dYdX Chain”). However, the applicable governance community has the ability to create and modify equity tiers and block rate limits as well as update existing placements.

Why am I receiving the below error when placing an isolated margin order?

You may the below error "Your order is below the minimum collateral requirement for isolated margin orders. Isolated margin orders require at least $20.00 of collateral".

This is related to Equity Tiers and Isolated Positions.

Each isolated position is individually subject to equity tier limits. Therefore, to open an isolated position via a long-term order, there must be at least $20 USDC of margin backing the position. If the isolated position has <$20 of margin backing it, its long term/conditional orders will fail.

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