a) Plans Offered

UBS has established several equity participation plans to further align the long-term interests of executives, managers, staff and shareholders. The plans are offered to eligible employees in approximately 50 countries and are designed to meet the complex legal, tax and regulatory requirements of each country in which they are offered. The explanations below describe the most significant plans in general, but specific plan rules and investment offerings may vary by country.

Equity Plus (EP): This voluntary plan gives eligible employees the opportunity to purchase UBS shares at fair market value on the purchase date and receive at no additional cost two UBS options for each share purchased, up to a maximum annual limit. The options have a strike price equal to the fair market value of the stock on the date the option is granted. Share purchases can be made annually from bonus compensation or quarterly based on regular deductions from salary. Shares purchased under Equity Plus are restricted from sale for two years from the time of purchase, and the options granted have a two-year vesting requirement and generally expire from ten years to ten and one-half years after the date of grant.

Discounted purchase plans: Up to and including 2005, selected employees in Switzerland were entitled to purchase a specified number of UBS shares at a predetermined discounted price each year. The number of shares that could be purchased depended on rank. Any such shares purchased must be held for a specified period of time. The discount is recorded as compensation expense. No new awards will be made under this plan.

Equity Ownership Plan (EOP): Selected personnel receive between 10% and 45% of their performance-related compensation in UBS shares or notional UBS shares instead of cash, on a mandatory basis. Up to and including 2004, participants in certain countries were eligible to receive a portion of their award in UBS shares (with a matching contribution in UBS options) or in Alternative Investment Vehicles (AIVs) (generally money market funds, UBS and non-UBS mutual funds and other UBS sponsored funds). In 2002 and 2003, certain employees received UBS options instead of UBS shares for a portion of their EOP award. In 2005, options were not granted as part of EOP and awards were generally made in UBS shares. EOP awards vest in one-third increments over a three-year vesting period. Under certain conditions, these awards are fully forfeitable by the employee.

Key employee option plans: Under these plans, key and high potential employees are granted UBS options with a strike price not less than the fair market value of the shares on the date the option is granted. Option grants generally vest in one-third increments over a three-year vesting period and generally expire from ten years to ten and one-half years after the grant date. One option gives the right to purchase one registered UBS share at the option’s strike price.

Other plans: UBS sponsors a deferred compensation plan for selected eligible employees. Generally, contributions are made on a voluntary and tax deferred basis, and participants are allowed to notionally invest in AIVs. No additional company match is granted, and the plan is generally not forfeitable. In addition, UBS also grants other compensation awards to new recruits and key employees, generally in the form of UBS shares or options.

UBS satisfies share delivery obligations under its option based participation plans either by purchasing UBS shares in the market on grant date or shortly thereafter or through the issuance of new shares. At exercise, shares held in treasury are delivered, or alternatively newly issued, to the employee against receipt of the strike price. As at 31 December 2005, UBS was holding approximately 56 million shares in treasury which is expected to be sufficient for anticipated employee exercises in the next year.

b) UBS share awards

Movements in shares granted under various equity participation plans described in Note 31a) are as follows:

UBS estimates the grant date fair value of shares awarded during the year by using the average UBS share price on the grant date as quoted on the virtX.

The market value of shares vested was CHF 1,083 million, CHF 1,922 million and CHF 1,677 million for the years ended 31 December 2005, 31 December 2004 and and 31 December 2003, respectively.

The weighted average share price of options exercised during the year was CHF 106, CHF 93 and CHF 77 for the years ended 31 December 2005, 31 December 2004 and 31 December 2003, respectively. The following table provides additional information about option awards:

In addition, UBS receined cash of CHF 2,018 million and an income tax benefit of CHF 217 million from the exercise of share options for the year ended 31 December 2005. The intrinsic value of share-based liabilities (shares and options) paid for the years ended 31 December 2005, 31 December 2004 and 31 December 2003 was CHF 87 million, CHF 669 million and CHF 1,092 million, respectively.

The following tables summarize additional information about options outstanding and options exercisable at 31 December 2005:

d) Valuation

Upon adoption of IFRS 2 and SFAS 123-R, both titled Share-based Payment, on 1 January 2005, UBS conducted a review of its option valuation inputs to ensure they were in line with the guidance included in the two standards. As a result of that review, UBS now uses a mix of implied and historic volatility instead of solely historic volatility and specific employee exercise behavior patterns based on statistical data instead of a single expected life input to determine the fair value of the options. A more sophisticated option valuation model was concurrently introduced to better model the UBS-specific employee exercise behavior patterns. The overall change in fair value of the options in 2005 versus 2004 is primarily attributable to using implied instead of historic volatility. The use of market-implied volatility decreased the fair value of the option by approximately CHF 7 or 29% compared to using historic volatility. The remaining reduction in fair value of approximately CHF 2 is attributable to the introduction of the new valuation model which uses UBS-specific employee exercise behavior patterns rather than an expected life input, as well as all other input changes based on observable market factors.

The fair value of options granted during 2005 was determined using the following assumptions:

The valuation technique takes into account the specific terms and conditions under which the share options are granted such as the vesting period, forced exercises during the lifetime, and gain- and time-dependent exercise behavior. The expected term of each option is calculated, by means of Monte Carlo simulation, as the probability-weighted average of the time of exercise.

The term structure of volatility is derived from the implied volatilities of traded UBS options in combination with the observed long-term historic share price volatility. Dividends are assumed to grow at a 10% yearly rate over the term of the option.

The fair value of options granted during 2004 and 2003 was determined using a proprietary option pricing model, similar to an American-style binomial model, with the following assumptions:

The expected life was estimated on the basis of observed employee option exercise patterns. Volatility was derived from the observed long-term historic share price volatility aligned to the expected life of the option. Dividends were assumed to grow at a 10% yearly rate over the expected life of the option.

e) Compensation expense

Generally, under IFRS, for all employee share and option awards for which the underlying is UBS shares, UBS recognizes compensation expense over the requisite service period which is generally equal to the vesting period. Share and option awards typically have a three-year tiered vesting structure which means awards vest in one-third increments over that period. The total share-based compensation expense recognized for the years ended 31 December 2005, 31 December 2004 and 31 December 2003 was CHF 1,662 million, CHF 1,406 million and CHF 1,474 million, respectively. The total income taxes recognized in the Income statement in relation to these expenses were a benefit of CHF 431 million, CHF 64 million and CHF 197 million for the years ended 31 December 2005, 31 December 2004 and 31 December 2003, respectively.

For the years ended 31 December 2005 and 31 December 2004, virtually all of the expense recorded for share-based payments was related to equity settled plans. For the year ended 31 December 2003, the expense recorded for equity-settled plans was CHF 1,247 million. At 31 December 2005 and 31 December 2004, the total liability related to vested and unvested cash-settled share-based plans was insignificant.

At 31 December 2005, total compensation cost related to non-vested awards not yet recognized in the Income statement is CHF 1,252 million, which is expected to be recognized in Personnel expenses over a weighted average period of 1.87 years.