[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [local‑first/Owner](https://evolu.dev/docs/api-reference/common/local-first/Owner) › OwnerUsage

Defined in: [packages/common/src/local-first/Owner.ts:550](https://github.com/evoluhq/evolu/blob/037c390af081e9944d616ff298a729515c5c5ab7/packages/common/src/local-first/Owner.ts#L550)

Storage usage and timestamp bounds for an [Owner](https://evolu.dev/docs/api-reference/common/local-first/Owner/interfaces/Owner).

Storage and relay implementations use this metadata for quota enforcement and
timestamp insertion strategies.

## Properties

<a id="firsttimestamp"></a>

### firstTimestamp

```ts
readonly firstTimestamp:
  | Uint8Array<ArrayBufferLike> & Brand<"Length16"> & Brand<"TimestampBytes">
  | null;
```

Defined in: [packages/common/src/local-first/Owner.ts:570](https://github.com/evoluhq/evolu/blob/037c390af081e9944d616ff298a729515c5c5ab7/packages/common/src/local-first/Owner.ts#L570)

Tracks the earliest timestamp for timestamp insertion strategies.

---

<a id="lasttimestamp"></a>

### lastTimestamp

```ts
readonly lastTimestamp:
  | Uint8Array<ArrayBufferLike> & Brand<"Length16"> & Brand<"TimestampBytes">
  | null;
```

Defined in: [packages/common/src/local-first/Owner.ts:577](https://github.com/evoluhq/evolu/blob/037c390af081e9944d616ff298a729515c5c5ab7/packages/common/src/local-first/Owner.ts#L577)

Tracks the latest timestamp for timestamp insertion strategies.

Free relays can use it to identify inactive accounts for cleanup.

---

<a id="ownerid"></a>

### ownerId

```ts
readonly ownerId: Uint8Array<ArrayBufferLike> & Brand<"Length16"> & Brand<"IdBytes"> & Brand<"OwnerIdBytes">;
```

Defined in: [packages/common/src/local-first/Owner.ts:552](https://github.com/evoluhq/evolu/blob/037c390af081e9944d616ff298a729515c5c5ab7/packages/common/src/local-first/Owner.ts#L552)

Binary identifier of the [Owner](https://evolu.dev/docs/api-reference/common/local-first/Owner/interfaces/Owner) this usage belongs to.

---

<a id="storedbytes"></a>

### storedBytes

```ts
readonly storedBytes: number & Brand<"NonNaN"> & Brand<"Finite"> & Brand<"Int"> & Brand<"NonNegative">;
```

Defined in: [packages/common/src/local-first/Owner.ts:567](https://github.com/evoluhq/evolu/blob/037c390af081e9944d616ff298a729515c5c5ab7/packages/common/src/local-first/Owner.ts#L567)

Total logical data bytes stored.

Measures only [EncryptedDbChange](https://evolu.dev/docs/api-reference/common/local-first/Storage/type-aliases/EncryptedDbChange) data and excludes [Storage](https://evolu.dev/docs/api-reference/common/local-first/Storage/interfaces/Storage)
implementation overhead such as indexes and skip-list columns. This makes
the measurement consistent across storage implementations and suitable
for:

- **Predictable measurement** - same data = same byte count across all
  instances
- **Quota enforcement** - limits independent of storage implementation
- **Overhead tracking** - comparison with actual storage size