# Multi-Tenant Application Security Cheat Sheet — 5. API Security & Rate Limiting

> Implement per-tenant rate limiting and quotas. Apply tenant-specific API throttling. Validate tenant context on every API request. Use separate API keys per tenant. Implement tenant-aware request signing for B2B APIs. Tenant-Aware Rate Limiting Bounded code example (external data; do not execute aut

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-owasp-72fa960930fa676b6802>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.522724+00:00`
- Tags: `reference-seed`, `owasp`, `cheatsheets`, `multi-tenant`, `application`, `security`, `cheat`, `sheet`, `api`, `rate`, `limiting`

## Provenance

- Source: <https://github.com/OWASP/CheatSheetSeries/blob/07111ee754e832e335377ac64fd0f8f848d9029c/cheatsheets/Multi_Tenant_Security_Cheat_Sheet.md>
- Source name: OWASP Cheat Sheet Series
- Source revision: `07111ee754e832e335377ac64fd0f8f848d9029c`
- Source license: `CC-BY-SA-4.0`
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## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Implement per-tenant rate limiting and quotas. Apply tenant-specific API throttling. Validate tenant context on every API request. Use separate API keys per tenant. Implement tenant-aware request signing for B2B APIs.

Tenant-Aware Rate Limiting

Bounded code example (external data; do not execute automatically):
```python
import time
from dataclasses import dataclass
from enum import Enum

class TenantTier(Enum):
    FREE = "free"
    STARTER = "starter"
    BUSINESS = "business"
    ENTERPRISE = "enterprise"

@dataclass
class RateLimitConfig:
    requests_per_minute: int
    requests_per_day: int
    burst_size: int

TIER_LIMITS = {
    TenantTier.FREE: RateLimitConfig(60, 1000, 10),
    TenantTier.STARTER: RateLimitConfig(300, 10000, 50),
    TenantTier.BUSINESS: RateLimitConfig(1000, 100000, 100),
    TenantTier.ENTERPRISE: RateLimitConfig(5000, 1000000, 500),
}

class TenantRateLimiter:
    """Per-tenant rate limiting with tier support."""

    def __init__(self, redis_client):
        self.redis = redis_client

    async def check_rate_limit(self, tenant_id: str, tenant_tier: TenantTier) -&gt; dict:
        """Check and update rate limit for tenant."""
        config = TIER_LIMITS[tenant_tier]
        n
```

Attribution: Adapted from OWASP Cheat Sheet Series under CC-BY-SA-4.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.