A company's monopoly power can be measured not just by its pricing power, but by the 'noneconomic costs' it imposes on society. Dominant platforms can ignore negative externalities, like their product's impact on teen mental health, because their market position insulates them from accountability and user churn.

In its failed merger attempt, Cisco argued its market competitors included Sam's Club, a claim regulators rejected. This illustrates that the core of an antitrust case is often not the raw market share number, but the highly debatable and often opaque definition of the market itself, which can be skewed by paid economists.

Courts are forcing Apple to abandon its 30% revenue-sharing model for external payments. New rules mandate that fees must align with the actual costs of providing the service, like a toll road, rather than being a tax on the developer's overall economic success.

While AI shopping agents promise to protect consumer privacy by abstracting away direct retailer relationships, this is a false dawn. Power will likely centralize with the major tech companies providing these agents, not empower individual users with decentralized control. The battle for "owning the customer" simply moves to a new layer.

Laws intended for copyright, like the DMCA's anti-circumvention clause, are weaponized by platforms. They make it a felony to create software that modifies an app's behavior (e.g., an ad-blocker), preventing competition and user choice.

Thompson critiques Apple's lucrative services strategy as a shift from creating the best products to "harvesting the profits from other companies' innovations." The argument is that this rent-seeking behavior is corrosive to the company's core DNA of product excellence and innovation.

A toll is a fixed fee for a specific service, like using a road. A tax is a percentage of the economic value created. Apple's 30% cut is framed as a tax because it scales with a developer's success, rather than reflecting Apple's actual, relatively fixed costs for facilitating the transaction.

By mandating its own WebKit engine and banning more capable alternatives on iOS, Apple prevents web applications from competing effectively with native apps, pushing developers toward its lucrative App Store ecosystem.

Amazon is suing Perplexity because its AI agent can autonomously log into user accounts and make purchases. This isn't just a legal spat over terms of service; it's the first major corporate conflict over AI agent-driven commerce, foreshadowing a future where brands must contend with non-human customers.