version: "1.0.0"

Apollo Search

Search Apollo's 210M+ contacts and 35M+ companies to build targeted account and contact lists. Covers key endpoints, filters, proven configurations, and when to use Apollo vs alternatives.

Key Endpoints

Search (Free -- No Credits)

`POST /mixed_people/api_search` -- Search people database. Returns IDs and basic info but NOT emails/phones. Requires master API key.

curl -X POST https://api.apollo.io/api/v1/mixed_people/api_search \
  -H "Content-Type: application/json" \
  -H "x-api-key: YOUR_KEY" \
  -d '{
    "person_titles": ["VP Sales", "Head of Growth"],
    "person_seniorities": ["vp", "director"],
    "organization_num_employees_ranges": ["51,200"],
    "per_page": 100, "page": 1
  }'

Pagination: 100/page, max 500 pages = 50,000 records.

Search Companies (Costs Credits)

`POST /mixed_companies/search` -- Search company database. Returns partial data.

GOTCHA: Response uses "accounts" key, NOT "organizations". Missing funding, revenue, and tech stack -- use enrichment after search for full data.

curl -X POST https://api.apollo.io/api/v1/mixed_companies/search \
  -H "Content-Type: application/json" \
  -H "x-api-key: YOUR_KEY" \
  -d '{
    "q_organization_keyword_tags": ["saas"],
    "organization_num_employees_ranges": ["51,200", "201,500"],
    "organization_locations": ["United States"],
    "per_page": 100, "page": 1
  }'

Enrich (Costs Credits)

GOTCHA: Bulk org enrichment returns STRIPPED-DOWN data -- missing latest_funding_stage, total_funding, annual_revenue, technology_names[]. For full firmographic data, use single GET /organizations/enrich?domain=X instead.

Standard Workflow: Search Then Enrich

1. Search with POST /mixed_people/api_search (free, no credits)
2. Collect IDs from search results
3. Bulk enrich with POST /people/bulk_match (10 IDs per call, costs credits)
4. Get full profiles with emails, phone numbers, LinkedIn URLs, employment history

Never enrich individual search results one-by-one. Always batch into groups of 10.

Top 20 Filters

Company Filters

People Filters

Employee Count Ranges (API Values)

"1,10"          Micro / Startup
"11,50"         Small business
"51,200"        Growth stage
"201,500"       Mid-market
"501,1000"      Upper mid-market
"1001,5000"     Enterprise
"5001,10000"    Large enterprise
"10001,50000"   Mega enterprise

Proven Search Configurations

Config 1: Referral Ceiling Founders (Frontal's best segment)

COMPANY:
  Employees:    10-200
  Revenue:      $1M-$10M
  Industry:     Computer Software, Internet, IT & Services
  Funding:      Seed, Series A
  Location:     US, UK, Western Europe
  Sales Dept:   0-2 headcount (no/tiny sales team = referral-dependent)
 
PEOPLE:
  Titles:       Founder, Co-Founder, CEO, Managing Director, Owner
  Seniority:    Owner/Founder, C-Suite

Config 2: Failed DIY Outbound (60% progression, educated buyer)

COMPANY:
  Employees:    10-100
  Revenue:      $1M-$10M
  Technologies: Apollo, Lemlist, Instantly, Outreach, SalesLoft, LinkedIn Sales Navigator
  Location:     US, Canada, UK
  Sales Dept:   1-5 headcount
 
PEOPLE:
  Titles:       VP Sales, Head of Sales, Head of Growth, CEO, Founder, Director of Sales
  Seniority:    VP, Director, C-Suite, Owner/Founder

Config 3: Enterprise B2C (reference)

COMPANY:
  Employees:    501+
  Revenue:      $100M+
  Industry:     Financial Services, Automotive, Retail, Insurance, Pharma, Consumer Services, Telecom, Real Estate
  Location:     United States
 
PEOPLE:
  Titles:       CMO, VP Growth, Head of Brand, Director Brand, Director SEO, Head of SEO
  Seniority:    C-Suite, VP, Director
  Department:   Marketing

Rate Limits

• Fixed-window strategy (per minute, per hour, per day)
• Limits vary by pricing plan tier
• Bulk endpoints: 50% of single endpoint's per-minute rate, 100% of hourly/daily
• Check your limits: POST /usage_stats/api_usage_stats
• 429 response = rate limited. Back off and retry.

API Key Types

People API Search (/mixed_people/api_search) requires a master key.

Headers (all requests):

Content-Type: application/json
Cache-Control: no-cache
x-api-key: YOUR_API_KEY

Filter Building Process

1. Start broad -- industry + employee count + location
2. Check result count -- target 500-5,000 companies
3. Add keywords to narrow (Industry & Keywords filter)
4. Add signals -- technology, intent, job postings
5. Add people filters last -- title + seniority
6. Too few results (<500)? Loosen employee range or remove a keyword
7. Too many (>10,000)? Add funding stage or department headcount

Result Count Guidelines

< 500 companies     → Too narrow, loosen filters
500-2,000           → Good for targeted campaign
2,000-5,000         → Good for broad campaign
5,000-10,000        → Consider splitting into sub-segments
10,000+             → Too broad, add more filters

Apollo vs Lima Data vs Exa

General rule: Use Apollo to BUILD the list (search + filter). Use Lima Data to ENRICH the list (find emails). Use Exa when Apollo's database does not have what you need.

Gotchas

1. Industry is self-reported -- companies pick their own LinkedIn industry. "Information Technology & Services" is a catch-all.
2. Revenue is estimated -- unreliable for private companies under $10M.
3. Technologies = website tracking only -- detects scripts/pixels on the website. Internal tools (Slack, Notion) will not appear.
4. Employee count lags -- may be 3-6 months behind for fast-growing startups.
5. Department headcount is directional -- estimated from LinkedIn profiles. Small depts (1-3) most accurate.
6. Funding recency matters -- Series A from 5 years ago is very different from last quarter.
7. Job Postings = active only -- companies that just filled a role disappear from this filter.
8. Buying Intent requires Organization plan -- not available on Professional tier.
9. Search does not return emails -- must use enrichment endpoint after search.
10. No dedup on account/contact creation -- Apollo will create duplicates unless you set run_dedupe=true.

Proxy Filter Strategies

Apollo does not have a "who does this company sell to?" filter. Use proxies:

Companies selling to SMB:

• Keywords: "small business", "SMB", "SME", "freelancer", "solopreneur"
• Tech stack: Stripe, Mailchimp, Calendly, QuickBooks, Gusto
• Company size: 11-200 employees (SMB sellers are usually SMB themselves)

Companies with outbound motion:

• Job Postings: "SDR", "BDR", "Sales Development"
• Tech stack: Outreach, SalesLoft, Apollo, Lemlist, Instantly
• Sales dept headcount: 1-20

Companies selling to a vertical:

• Keywords: "[vertical]" + "platform" OR "solution" OR "software"
• Industry: Computer Software (NOT the vertical itself -- that finds the buyers, not the sellers)

References

• Apollo API full reference: frontal-tools/skills/apollo/SKILL.md
• Apollo filters reference: frontal-tools/skills/apollo-filters/SKILL.md
• Lima Data API: frontal-tools/skills/lima-data/SKILL.md

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