---
title: "SAX: Methodology"
description: "SAX is maintained by Bratislava Stock Exchange and covers Slovak equity benchmark. How the index selects and weights its constituents, and what it measures."
canonical: https://www.getswoopr.com/stocks/indexes/sax/
source: "Swoopr Investment: https://www.getswoopr.com"
---

# SAX: What It Measures and How It Is Built

## Direct Answer

> The SAX is a rule-based measurement of Slovak equity benchmark, maintained by Bratislava 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 SAX covers Slovak equity benchmark, within the Slovakia market. Bratislava 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

Capital weighted: the market capitalisation of the selected shares is compared with that of the same set on a reference day. The weight of any company in the index base must not exceed 20%.

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

Only companies listed on the regulated market can be included in the SAX index base.

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.

## When the membership is revised

The base is revised regularly twice a year, and an updated base takes effect on the first stock exchange day of February and August.

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

Besides price changes the index includes dividend payments and revenue from changes in share capital, and the exchange states it is not an authorised or registered administrator of SAX under the EU Benchmarks Regulation.

## References

- [Bratislava Stock Exchange: Bratislava Stock Exchange SAX Index page](https://www.bsse.sk/bcpb/en/indices/sax-index/), as published 2026. Every rule described on this page is taken from this document.

## Current SAX constituents

Bratislava Stock Exchange publishes and licenses the SAX constituent list. Swoopr does not republish it here. The provider's own page is the authoritative source for current membership and weights.

[Bratislava Stock Exchange: official SAX page](https://www.bsse.sk/bcpb/trhove-data/index-sax/)

## Related reading

- [All stock market indexes](https://www.getswoopr.com/stocks/indexes/): how indexes are built, weighted and revised.
- [Europe indexes](https://www.getswoopr.com/stocks/indexes/europe/): others covering the same region.
- [Index concentration](https://www.getswoopr.com/technical-analysis/market-concentration/index-concentration/): measuring how much of an index sits in its largest holdings.
- [Index rebalancing and inclusion effects](https://www.getswoopr.com/stocks/corporate-actions-catalysts/index-rebalancing-and-inclusion-effects/): what happens to a stock when index membership changes.

## Frequently Asked Questions

### Who maintains the SAX?

Bratislava Stock Exchange maintains the SAX and publishes the methodology document that defines its eligibility and weighting rules.

### What does the SAX measure?

It measures Slovak 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 SAX constituents?

Bratislava Stock Exchange publishes the current constituent list. Swoopr does not republish it, because index providers license constituent data and Swoopr holds no such licence.

## About the author

The [Swoopr Editorial Team](https://www.getswoopr.com/authors/swoopr-editorial-team/) writes Swoopr Investment's educational library, covering market structure, analysis methods and the mechanics behind the numbers investors read every day.

Our [editorial policy](https://www.getswoopr.com/legal/editorial-policy/) and [corrections policy](https://www.getswoopr.com/legal/corrections-policy/) set out how this content is produced, reviewed and fixed when it is wrong.