Direct Answer
The CROBEX is a rule-based measurement of Croatian equity benchmark, maintained by Zagreb Stock Exchange. Like every index it owns nothing: it is a number produced by applying a published weighting formula to a selected list of companies, revised on a schedule the provider sets.
What this index covers
The CROBEX covers Croatian equity benchmark, within the Croatia market. Zagreb Stock Exchange defines which securities are eligible, how they are selected from that pool, and how much each one contributes to the published number.
The index name does not state a fixed company count, so the number of constituents follows the eligibility rules rather than a target.
How constituents are weighted
Price index weighted by free float market capitalisation, with no share allowed above 10% of the total, enforced through weighting factors set six business days before the regular revision. Free float excludes treasury shares and holders of 5% or more unless they are pension or investment funds.
The weighting method is the single biggest driver of how an index behaves. Two indexes covering the same market can diverge for years purely because they weight differently, which is why comparing index levels without knowing the method tells you very little.
What qualifies for inclusion
Regulated market shares that traded on more than 75% of trading days in the prior six months, ranked 50% on free float market capitalisation share and 50% on order book turnover share. The index holds 15 to 25 shares, one class per issuer, and companies in pre bankruptcy, bankruptcy or liquidation proceedings are ineligible.
Eligibility rules are the part of an index most readers never look at and the part that decides what it can possibly measure. A screen that excludes a whole sector, or admits only one listing venue, shapes the result far more than any day of trading does.
How long a listing must exist first
A new share can enter through an extraordinary revision if it trades on 100% of sessions in its first 30 days after listing. At the next regular revision the six month look back counts only from the listing date.
A seasoning rule is why a large new listing does not appear in an index the week it starts trading. It is a deliberate lag, and it means an index can under-represent a fast-growing part of the market for months at a time.
When the membership is revised
Regular revisions follow the close on the third Friday of March, June, September and December. March and September revisions use six months of data and can change composition, while June and December only update share numbers, free float and weighting factors.
Reconstitution is the one date an index changes shape by design rather than by price. Funds tracking it have to trade toward the new membership, which is why the schedule matters to anyone holding the tracker rather than only to the provider.
The rule that surprises people
A 23 over 28 tolerance zone applies: the top 22 ranked shares enter directly and the last three places go to the shares ranked 23rd to 28th, with preference to existing constituents.
References
- Zagreb Stock Exchange: Zagreb Stock Exchange Resolution on the CROBEX index, as published 2025. Every rule described on this page is taken from this document.
Current CROBEX constituents
Zagreb Stock Exchange publishes and licenses the CROBEX constituent list. Swoopr does not republish it here. The provider's own page is the authoritative source for current membership and weights.
Related reading
- All stock market indexes: how indexes are built, weighted and revised.
- Europe indexes: others covering the same region.
- Index concentration: measuring how much of an index sits in its largest holdings.
- Index rebalancing and inclusion effects: what happens to a stock when index membership changes.
Frequently Asked Questions
Who maintains the CROBEX?
Zagreb Stock Exchange maintains the CROBEX and publishes the methodology document that defines its eligibility and weighting rules.
What does the CROBEX measure?
It measures Croatian equity benchmark. The index is a calculated number applying a weighting formula to a selected list of companies, and it holds nothing itself.
Where can I see the current CROBEX constituents?
Zagreb Stock Exchange publishes the current constituent list. Swoopr does not republish it, because index providers license constituent data and Swoopr holds no such licence.