Buyers and sellers took turns in most of the week but at the close, optimists prevailed, pulling the shares to the new record.
The week was marked by releases of first-quarter economic results of companies and the privatisation of part of a state-owned stake in power producer CEZ.
Several new investment recommendations appeared as well. Shares of petrochemical group Unipetrol were the hit of the week as they gained an exceptional 11 percent to Kc271.4.
Eni of Italy has apparently doubled its stake in the Czech company Ceska rafinerska (CeR) to 35 percent from 16.33 percent within its expansion programme in central and eastern Europe.
The value of the transaction is put at some EUR500m (Kc14.1bn). Unipetrol owns 51 percent of CeR, which operates refineries in Litvinov and Kralupy.
This would raise the value of Unipetrol's stake to Kc45bn, while the current market capitalisation for the whole Unipetrol stands at around Kc49bn.
Unipetrol posted net earnings of Kc1.564bn in Jan to March this year, an improvement from Kc786m profit in the same year-ago period.
CEZ shed 0.9 percent to Kc1,067 despite continuing purchases of the stock by CEZ itself.
The Czech government at an extraordinary meeting okayed the sale of 7 percent of power producer CEZ shares through the capital market.
The government did not disclose details of the transaction, for which it was criticised on the market. Speculations also appeared about an intermediary whose income from the transaction may reach up to Kc4bn.
Transparency and fair conditions can hardly be talked about, Raiffeisenbank analyst Ales Michl commented on CEZ privatisation.
CEZ also released first-quarter economic results this week. CEZ raised first-quarter net profit by 25.1 percent year-on-year to Kc12.98bn this year, according to consolidated unaudited results. This was more than analysts had expected.
Textile company Pegas Nonwovens added 5.3 percent in the week - to Kc812. Komercni banka (KB) issued its first recommendation for Pegas stock. It advised to buy the stock and put its target price at Kc908 apiece.
Several new investment recommendations concerning KB appeared. The most favourable was from CAIB analysts who put the target price at Kc5,353 when including dividends. In contrast, KBC/Patria lowered the target price from Kc4,324 to Kc4,231. KB shares rose by 2.1 percent to Kc4,058 in the week.
Zentiva, in contrast, lost 4.7 percent to Kc1,403. Zentiva raised net profit by 1.6 percent to Kc518.9m in the first quarter and its sales grew by 6.3 percent to roughly Kc3.38bn. The data, however, were worse than analysts had expected.
Share trading at Kc22.3bn was much higher than this year's average. The previous volume was at Kc16.6bn, but there were only four trading days in that week.