VOL. XCIV, NO. 247

★ WIDE MOAT STOCKS COMPARISON ★

NO ADVICE

Wednesday, December 31, 2025

Stock Comparison

American Tower Corporation vs CoStar Group, Inc.

Compare moat strength, market structure, and segment coverage to understand how each company defends its edge.

American Tower Corporation

AMT · New York Stock Exchange

Market cap (USD)
SectorReal Estate
CountryUS
Data as of2025-12-31
Moat score
76/ 100

Weighted average of segment moat scores, combining moat strength, durability, confidence, market structure, pricing power, and market share.

Full stock profile

Dive deeper into American Tower Corporation's moat claims, evidence, and risks.

View AMT analysis

CoStar Group, Inc.

CSGP · NASDAQ

Market cap (USD)$28.6B
SectorReal Estate
CountryUS
Data as of2025-12-29
Moat score
75/ 100

Weighted average of segment moat scores, combining moat strength, durability, confidence, market structure, pricing power, and market share.

Full stock profile

Dive deeper into CoStar Group, Inc.'s moat claims, evidence, and risks.

View CSGP analysis

Comparison highlights

  • Moat score gap: American Tower Corporation leads (76 / 100 vs 75 / 100 for CoStar Group, Inc.).
  • Segment focus: American Tower Corporation has 3 segments; CoStar Group, Inc. has 6 segments (39% in Multifamily (Apartments.com Network)).
  • Primary market structure: Oligopoly vs Oligopoly. Pricing power: Moderate vs Strong.
  • Moat breadth: American Tower Corporation has 6 moat types across 4 domains; CoStar Group, Inc. has 9 across 4.

Primary market context

American Tower Corporation

U.S. & Canada Communications Sites

Market

Wireless communications site leasing (macro towers, rooftops and DAS)

Geography

United States and Canada

Customer

Wireless carriers and other tenants (broadcast, data, government/municipal)

Role

Independent owner/operator of communications real estate (towerco)

CoStar Group, Inc.

Multifamily (Apartments.com Network)

Market

Online multifamily rental marketplaces and advertising

Geography

United States

Customer

Two-sided (renters + property managers/owners)

Role

Marketplace (subscription advertising + workflow tools)

Revenue share

39%

Side-by-side metrics

American Tower Corporation
CoStar Group, Inc.
Ticker / Exchange
AMT - New York Stock Exchange
CSGP - NASDAQ
Market cap (USD)
n/a
$28.6B
Sector
Real Estate
Real Estate
HQ country
US
US
Primary segment
U.S. & Canada Communications Sites
Multifamily (Apartments.com Network)
Market structure
Oligopoly
Oligopoly
Market share
n/a
n/a
HHI estimate
n/a
n/a
Pricing power
Moderate
Strong
Moat score
76 / 100
75 / 100
Moat domains
Demand, Legal, Supply, Network
Supply, Network, Demand, Legal
Last update
2025-12-31
2025-12-29

Moat coverage

Shared moat types

No overlap yet.

American Tower Corporation strengths

Long Term ContractsPermits Rights Of WayPhysical Network DensitySwitching Costs GeneralInteroperability HubCapacity Moat

CoStar Group, Inc. strengths

Capex Knowhow ScaleData Network EffectsData Workflow LockinDe Facto StandardIP Choke PointTwo Sided NetworkBrand TrustSuite BundlingEcosystem Complements

Segment mix

American Tower Corporation segments

Full profile >

U.S. & Canada Communications Sites

Oligopoly

n/a

International Communications Sites

Oligopoly

n/a

Data Centers

Competitive

n/a

CoStar Group, Inc. segments

Full profile >

CoStar (commercial real estate info & analytics)

Oligopoly

37.3%

Information Services (lease management software + international info)

Competitive

5%

Multifamily (Apartments.com Network)

Oligopoly

39%

LoopNet (commercial property marketing marketplace)

Oligopoly

10.3%

Residential (Homes.com + OnTheMarket)

Oligopoly

3.7%

Other Marketplaces (Ten-X, Land.com, BizBuySell, etc.)

Competitive

4.8%

Want the full wide moat stocks list?

Browse the full ranking of wide moat stocks, updated with moat scores and segment context.

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Curation & Accuracy

This directory blends AI‑assisted discovery with human curation. Entries are reviewed, edited, and organized with the goal of expanding coverage and sharpening quality over time. Your feedback helps steer improvements (because no single human can capture everything all at once).

Details change. Pricing, features, and availability may be incomplete or out of date. Treat listings as a starting point and verify on the provider’s site before making decisions. If you spot an error or a gap, send a quick note and I’ll adjust.