ICOs and STOs: two ways to sell a token, two different rulebooks
One raised billions with almost no securities compliance. The other exists because regulators noticed.
At a glance
- An ICO sells a token directly to the public, historically with little to no securities registration — the model behind both 2017's boom and its wave of enforcement actions.
- An STO structures the same kind of raise as a registered or exempt securities offering from the start, trading reach for legal durability.
- Most tokens sold in ICOs were later found by regulators to be unregistered securities; an STO is designed specifically to avoid that outcome.
An initial coin offering is, mechanically, simple: a project sells a newly created token directly to the public in exchange for another cryptocurrency or fiat currency, usually before the network or product the token is meant to support fully exists. The model exploded in 2017, when it let projects raise enormous sums directly from retail buyers worldwide with none of the underwriting, disclosure, or gatekeeping a traditional public offering requires.
That absence of gatekeeping was the entire appeal, and also the entire problem. Because most ICO tokens were marketed on the expectation of profit driven by the promoters' efforts — the classic test for a security — regulators in the US and elsewhere subsequently found the large majority of them to be unregistered securities offerings, regardless of what the project itself called the token. Some of the largest enforcement actions in crypto history trace directly back to a 2017-era ICO.
A security token offering starts from the opposite assumption: that the token is, or may be treated as, a security, and structures the raise accordingly from day one. That usually means selling through an existing securities exemption — a private placement to accredited investors, a registered public offering, or a regulated crowdfunding exemption — with the disclosure, transfer restrictions, and investor-qualification checks those exemptions require.
The practical difference shows up immediately in who can buy. An ICO, historically, would sell to essentially anyone with a wallet and an internet connection. An STO is typically restricted to accredited or otherwise qualified investors from the outset, precisely because it's built on the same exemptions covered elsewhere in this primer — the same instrument, sold through the compliant version of the process rather than around it.
What an STO buys the issuer is legal durability. A token sold through a proper securities exemption, with the required disclosures and transfer restrictions in place, is far less exposed to the retroactive enforcement risk that hit so many 2017-era ICOs years after the money was already raised and spent. What it costs the issuer is reach: the same rules that reduce legal risk also cut the buyer pool from “anyone” down to a much smaller, verified group.
The pure ICO model, as it existed in 2017, has largely disappeared for exactly this reason. It's now widely understood to expose an issuer to years of retroactive legal risk for a fundraising method that was only ever fast because it skipped the steps an STO puts back in.
Key terms
- ICO
- Initial coin offering — selling a new token directly to the public, historically with little to no securities registration.
- STO
- Security token offering — structuring a token sale as a registered or exempt securities offering from the outset.
- Howey test
- The US legal test for whether an arrangement is an investment contract, and therefore a security, based on an investment of money in a common enterprise with an expectation of profit from others' efforts.
Frequently asked
Are all ICOs illegal?
Not inherently — the issue is usually failing to register or qualify for an exemption when the token meets the legal test for a security, not the ICO format itself; a small number of token sales have been structured specifically to avoid that classification.
Can an ordinary retail investor buy into an STO?
Usually not directly — most STOs use exemptions restricted to accredited investors, though regulated crowdfunding exemptions in some jurisdictions do allow limited retail participation.
Why did ICOs largely disappear after 2017-2018?
A wave of enforcement actions made clear that most ICO tokens were unregistered securities, which made the format's core advantage — speed with minimal compliance — no longer worth the retroactive legal exposure it created.