Frequently Asked Questions

1 What is ISO 500 and why is it important?

Türkiye's Top 500 Industrial Enterprises (ISO 500 and ISO Second 500) is a traditional survey that was initiated by the Istanbul Chamber of Industry (ICI) in 1968 in order to determine the giants of the Turkish industrial sector. Started with 100 largest enterprises, the scope of the study has been expanded to 1,000 enterprises over the years.

ISO 500, the oldest and most comprehensive study regarding the industrial sector in Türkiye, is ICI’s product with the greatest brand value.

Followed with deep interest by economists and the business world, ISO 500 provides substantial input to many academic and scientific studies as an important source of reference for monitoring the development story of the Turkish industrial sector.

2 What are the benefits of being in the ranking to companies?

Being listed in the ISO 500 rankings is considered an important source of reputation and contributes significantly to the promotion of companies both at home and abroad. Companies that succeed in being listed are also offered the opportunity to strengthen their corporate identity and brand value by using ISO 500 logos for a certain fee.

3 By what criterion is the ranking made?

Firms are sorted by their production-based sales (net) revenues. Production-based sales do not include goods that are sold as received (commercial goods) without going through the production process.

The lists subject to public release also include the ranks of the companies in terms of economic aggregates other than production-based sales (e.g. net sales, exports, number of employees).

4 Which companies can participate?

All companies operating in industrial sector (i.e., mining and quarrying, manufacturing and electricity generation) within the borders of Türkiye can participate in the ISO 500 survey. Companies whose main field of activity is agriculture, livestock, wholesale and retail trade, services, construction, finance, insurance, etc. are outside the scope of the survey.

As a condition of participating in the survey, a lower limit of production-based sales (net) is specified, which is updated every year. Companies whose production-based sales of the previous year are above that limit can fill out the questionnaire.

5 Is a separate questionnaire filled in for the ISO Second 500?

No. As the name suggests, this list, which includes companies that follow the ISO 500 and fall between the 501st and 1,000th ranks, is usually released to the public approximately one month after the ISO 500. However, all of the questionnaires are collected within the same period.

6 Is it necessary to be a member of the ICI to participate in the survey?

No. All industrial companies operating in Türkiye and meeting the relevant conditions (See Question 4) can participate in the ISO 500 survey. It is not necessary to be a member of the Istanbul Chamber of Industry.

7 Is participation in the survey mandatory for the companies?

No. Participating in the survey is completely voluntary and has no consequences for companies that do not.

8 Is it obligatory to share all the information requested in the survey with ISO?

All required information in the questionnaire should be submitted to the ICI. If there is any field in the questionnaire that is left blank, the survey cannot be completed and submitted.

However, the information provided in the survey is never disclosed to the public without the approval from the company. (For details on data subject to disclosure, see Question 9).

9 Is it possible for the company title and/or some information not to be disclosed to the public?

Since the purpose of the survey is to identify the largest companies operating in the industrial sector in Türkiye, companies that are not willing to disclose their titles or some other information are also included in the study. Although the figures of these companies are included in the aggregates, they are not disclosed to the public on a company basis.

The data subject to disclosure on a company basis are as follows:

  • Company Name
  • Production-Based Sales
  • Net Sales
  • Gross Value Added (in Producers’ Prices)
  • Equity Capital
  • Total Assets
  • Profit/Loss for the Period (Before Tax)
  • EBITDA (Earnings/Loss Before Interest, Tax, Depreciation and Amortization)
  • Exports
  • Average Number of Wage Employees

Companies participating in the survey may keep their data confidential under the following rules:

  • If a firm is not consent to the disclosure of either its production-based sales or net sales figures, then no information of that firm, nor the company title, will be disclosed.
  • The titles of the companies that prefer to disclose the production-based sales and net sales figures are also disclosed. Whether or not to disclose other information is at the company's discretion.
  • Even if the company chooses to remain anonymous, it is included in the ranking if its production-based sales is sufficient. However, all information, including the company title, appears as a hyphen (-). The firm's data is included in all aggregated figures.
  • If one of the production-based sales or net sales figures is disclosed, the other is not allowed to be kept confidential.
  • If a company has accepted the disclosure of its “profit/loss for the period” data, its gross value-added is also disclosed (gross value-added is automatically calculated using various figures provided by the firm as part of the survey).

10 How is the survey data processed? Is there a check/validation mechanism?

The data submitted as part of the ISO 500 questionnaire is subject to a thorough review by the ICI experts. The annual Corporate Tax e-Return for the survey year, which must also be submitted to ICI as a prerequisite of participating in the survey, is used to control the data.

In various cases, ICI experts may contact the company representative who filled out the questionnaire to request confirmation, clarification or correction regarding some data. The process is considered finalized when both parties agree on all the information stated in the questionnaire.

11 For what reasons may a company not be listed in the ISO 500 list?

If a company appears to meet the requirements to participate in the ISO 500 survey but is not listed in the ranking, this may be due to one of the following:

  • The survey form may not have been submitted to ICI until the deadline.
  • The company’s Production-Based Sales figure (see Question 3) for the respective year may not be sufficient for it to be listed in the ISO 500 or ISO Second 500.
  • The company may have preferred to keep its title confidential even though it is of sufficient size and has completed the survey application (see Question 9).

12 Are ISO 500 data revised after the results are announced?

No. After the survey results are presented to the public, the data are considered final and not subject to revision.