o

Rule 13d-1(b)

o

Rule 13d-1(c)

x

Rule 13d-1(d)

CUSIP No. 864909106

1.

Names of Reporting Persons

I.R.S. Identification No. of Above Person
R-TECH UENO, LTD. 
98-0394288

2.

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)

o

(b)

o

3.

SEC Use Only

4.

Citizenship or Place of Organization
JAPAN

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
2,485,150

6.

Shared Voting Power
0

7.

Sole Dispositive Power
2,485,150

8.

Shared Dispositive Power
0

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
2,485,150

10.

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)  o

11.

Percent of Class Represented by Amount in Row (9)
16.0%

12.

Type of Reporting Person (See Instructions)
CO

Item 1.

(a)

Name of Issuer
SUCAMPO PHARMACEUTICALS, INC.

(b)

Address of Issuer’s Principal Executive Offices
4520 EAST-WEST HIGHWAY

SUITE 300

BETHESDA, MD 20814

Item 2.

(a)

Name of Person Filing
R-TECH UENO, LTD.

(b)

Address of Principal Business Office or, if none, Residence
10F, YAMATO LIFE INSURANCE BLDG. 
1-1-7 UCHISAIWAICHO, CHIYODA-KU

TOKYO 100-0011, JAPAN

(c)

Citizenship
JAPAN

(d)

Title of Class of Securities
CLASS A COMMON STOCK

(e)

CUSIP Number
864909106

Item 3.

If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

(a)

o

Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b)

o

Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c)

o

Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

(d)

o

Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).

(e)

o

An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);

(f)

o

An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);

(g)

o

A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);

(h)

o

A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)

o

A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j)

o

Group, in accordance with §240.13d-1(b)(1)(ii)(J).

Not Applicable.

Item 4.

Ownership

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

(a)

Amount beneficially owned:

2,485,150

(b)

Percent of class:   

16.0%

(c)

Number of shares as to which the person has:

(i)

Sole power to vote or to direct the vote   

2,485,150

(ii)

Shared power to vote or to direct the vote    

0

(iii)

Sole power to dispose or to direct the disposition of   

2,485,150

(iv)

Shared power to dispose or to direct the disposition of   

0

Item 5.

Ownership of Five Percent or Less of a Class

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following   o.

Not Applicable

Item 6.

Ownership of More than Five Percent on Behalf of Another Person

Not Applicable

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person

Not Applicable

Item 8.

Identification and Classification of Members of the Group

Not Applicable

Item 9.

Notice of Dissolution of Group

Not Applicable

Item 10.

Certification

Not Applicable

Dated:  February 14, 2008

R-TECH UENO, LTD.

By:

/s/ Douglas W. Charnas

Name:

Douglas W. Charnas

Its:

Attorney In Fact

/s/ Yukiko Hashitera

Yukiko Hashitera

Representative Director