1. First Quarter 2005 Millipore Conference Call, April 21, 2005

2. 2 Forward-looking statements/risk factors In order to take advantage of the safe harbor provisions of the private securities litigation reform act of 1995, you should understand that we will be making forward-looking statements in this conference. These statements involve a number of risks and uncertainties, all of which are set forth in detail in our annual report on Form 10-K, subsequent quarterly reports on Form 10-Q, and our other SEC filings. We assume no obligation to update any forward-looking statement based on new information, future events or any other reason.

3. 3 Regulation G: Use of non-GAAP financial measures In addition to analyzing U.S. GAAP financial results, management also analyzes “non-GAAP” and “pro forma” financial measures as we believe these measures may allow for a better understanding of the underlying business trends. n “Constant currency” is a non-GAAP measure whereby foreign currency balances are translated, in all periods presented, at Millipore’s predetermined budgeted exchange rates for 2005, thus excluding the impact of fluctuations in the actual foreign currency rates. n Pro forma basis financial results reflect U.S. GAAP results, translated at actual rates of exchange and adjusted for unusual or non-operating items.

4. 4 Q1 2005 summary n 12% revenue growth over Q1, 2004 n 10% revenue growth in constant currency n GAAP earnings per share of $0.64 n Pro forma earnings per share of $0.77 n Biotechnology: 18% growth in constant currency n Life science: flat compared to Q1, 2004 n Other bioscience: 7% growth in constant currency

5. 5 Q1 revenue growth - by market Biotechnology $ 83$ 7018% Life science3030- Other bioscience109103 7% Total constant currency22220310% Foreign exchange2819 Total U.S. dollar$250$22212% Q1 $ in millions Q1 2005Q1 2004 % Growth

6. 6 Biotechnology – quarterly revenue growth and trends (in constant currencies) Quarterly Growth Q1 2003 – Q1 2005Revenues by Quarter Q1 2003 – Q1 2005 - $ Millions $90 $80 $70 $60 $40 $30 $20 $10 $0 ’03 ’04 $50 ’05

7. 7 Other bioscience – quarterly revenue growth and trends (in constant currencies) $120 $80 $60 $40 $20 $0 $100 Quarterly Growth Q1 2003 – Q1 2005Revenues by Quarter Q1 2003 – Q1 2005 - $ Millions ’03 ’04’05

8. 8 Life science – quarterly revenue growth and trends (in constant currencies) Quarterly Growth Q1 2003 – Q1 2005Revenues by Quarter Q1 2003 – Q1 2005 - $ Millions $120 $80 $60 $40 $20 $0 $100 ’03 ’04’05 29%

9. 9 Americas 46% Europe 36% Asia/Pacific 18% By Geography Q1 2005 revenues (in constant currencies) Biotechnology 37% Life science 14% Other bioscience applications 49% By Market Consumables and services 84% Equipment 16% By Product

10. 10 Revenue growth - by geographic region Americas$ 103$ 8916%16% Europe1039013%7% Asia/Pacific44433% 1% Total U.S. dollar$250$22212%10% % Growth %Growth Constant $ in millions Q1 2005 Q1 2004U.S. Dollars Currency

11. 11 Actual dollars (In millions, except per share data) Q1 2005Q1 2004 % Growth Sales$ 250.2$ 222.512% Gross profit136.1121.612% % of sales54.4%54.6% SG&A77.467.814% % of sales 31.0%30.5% R&D16.116.0-- % of sales 6.4%7.2% Operating income 42.637.8 13% % of sales17.0%17.0% Net income$ 32.3$ 27.219% EPS$ 0.64$ 0.5516% Q1 GAAP results

12. 12 Actual Dollars (In millions, except per share data) Q1 2005Q1 2004 % Growth Sales$ 250.2$ 222.512% Gross profit136.1121.612% % of sales54.4%54.6% SG&A*69.267.82% % of sales 27.6%30.5% R&D16.116.0-- % of sales 6.4%7.2% Operating income* 50.837.8 35% % of sales20.3%17.0% Net income*$ 38.8$ 27.243% EPS*$ 0.77$ 0.5540% *In Q1, 2005, pro forma results exclude pretax $4.5M expense related to CEO transition costs and $3.8M related to employee severance costs Q1 pro forma results*

13. 13 Currency effects – Q1 2005 Euro/Dollar 1/1/05 - 4/2/05 Yen/Dollar 1/1/05 - 4/2/05

14. 14 Updated Financial Guidance 2005 n Revenue growth: n Actual dollar: 8 to 10% n Constant currency: 6 to 8% n Gross margins: averaging 53.5% of revenue n SG&A: 29.5% of revenue n R&D: 7% of revenue n Contribution: approximately 17% of revenue n Pro forma EPS*: $2.45 to $2.50 per share n Capital expenditures $85M n Depreciation and amortization $46M n Cash from operations $165M to $175M *Excludes CEO transition costs and employee severance related costs

15. 15 New platform and product: Direct-Q® 3 system for lab water n Every lab needs purified water n Addresses specific need for pure and ultrapure water from single point of use n Very positive customer response at Pittcon launch n Saves time, improves productivity

16. 16 New platform and product: Pod filters

17. 17 Millipore’s disposable Pod filters improve biotech manufacturing productivity

18. 18 Q1 2005 and next steps Q1 2005 n Bioscience Division n Progress - n Growth strategy n Operational improvements: n Manufacturing n R&D n Top 100 Best Corporate Citizens (Business Ethics magazine) Next steps n June 29: analyst and investor meeting in New York City: n New growth strategies n Long-term outlook n Organization n New transparency