Here is a list of some of the challenges that companies may face when calculating diluted EPS under IAS 33, and how these can be overcome:

1. Identifying potentially dilutive securities: One of the main challenges in calculating diluted EPS is identifying all of the potentially dilutive securities that could impact the calculation. These securities include stock options, warrants, convertible bonds, and other securities that could be converted into ordinary shares. To overcome this challenge, companies must carefully review their financial statements and notes to identify all potentially dilutive securities.
2. Determining the impact of potentially dilutive securities: Once potentially dilutive securities have been identified, companies must determine their impact on the calculation of diluted EPS. This can be complex, as the impact of potentially dilutive securities can vary depending on factors such as the exercise price, maturity date, and conversion ratio. Companies may need to work with financial advisors or use specialized software to accurately calculate the impact of potentially dilutive securities.
3. Adjusting for changes in potentially dilutive securities: Another challenge is adjusting the calculation of diluted EPS for changes in potentially dilutive securities that occur during the period. For example, if a company issues new stock options during the period, this can impact the calculation of diluted EPS. To overcome this challenge, companies must carefully track changes in their potentially dilutive securities and adjust their calculation of diluted EPS accordingly.
4. Managing the impact of foreign currency fluctuations: If a company has operations in multiple countries or reports financial statements in multiple currencies, fluctuations in foreign currency exchange rates can impact the calculation of diluted EPS. To overcome this challenge, companies must carefully manage their currency risk and use appropriate hedging strategies to minimize the impact of currency fluctuations.
5. Ensuring compliance with regulatory requirements: Finally, companies must ensure that their calculation of diluted EPS is in compliance with all relevant regulatory requirements, including those set out in IAS 33. This may require working with external auditors or consulting with regulatory experts to ensure that all requirements are met.

Overall, calculating diluted EPS can be complex and challenging, but companies can overcome these challenges by carefully reviewing their financial statements, working with financial advisors or specialized software, tracking changes in potentially dilutive securities, managing currency risk, and ensuring compliance with regulatory requirements.