Fitch Affirms Guggenheim Structured Real Estate Funding 2006-4.

CHICAGO -- Fitch has affirmed all classes of Guggenheim Structured Real Estate Funding 2006-4, Ltd. and Guggenheim Structured Real Estate Funding 2006-4, LLC (Guggenheim 2006-4) as follows:

--$6,000,000 class S notes at 'AAA';

--$265,000,000 class A-1 notes at 'AAA';

--$36,250,000 class A-2 notes at 'AAA';

--$43,750,000 class B notes at 'AA';

--$26,875,000 class C notes at 'A+';

--$14,375,000 class D notes at 'A';

--$13,750,000 class E notes at 'A-';

--$13,750,500 class F notes at 'BBB+';

--$15,000,500 class G notes at 'BBB';

--$10,625,000 class H notes at 'BBB-'.

Deal Summary:

Guggenheim 2006-4 is a $500,000,000 revolving commercial real estate (CRE) cash flow collateralized debt obligation (CDO) that closed on Jan. 25, 2007. As of the August 20, 2007 trustee report and, based on Fitch categorization, the CDO was invested as follows: CRE bank loans (23.7%), CMBS (22.6%), CRE mezzanine loans (18.0%), CRE whole loans/A-notes (16.6%), CRE CDOs (9.7%) and CRE B-notes (9.4%). The CDO is also permitted to invest in CTLs, REIT Debt and synthetic securities.

The portfolio is selected and monitored by GSREA, LLC (GSREA). Guggenheim 2006-4 has a five-year reinvestment period during which, if all reinvestment criteria are satisfied, principal proceeds may be used to invest in substitute collateral. The reinvestment period ends in February 2012.

Collateral Asset Manager:

Through its two private equity funds, Guggenheim Structured Real Estate (GSRE) is a private investor in commercial real estate debt, specializing in high-quality income-producing U.S. properties with experienced sponsorship. GSRE funds are managed by GSREA, both of which are affiliated with Guggenheim Partners, LLC (GP), a diversified financial services firm with more than 525 employees and over $125 billion of assets under supervision. The two equity funds have over $1.1 billion of private equity and have made approximately $7.0 billion of investments. None of the funds' investments have had losses or delinquencies.

Fitch rates GSREA a 'CAM2' U.S. CRE CDO Asset Manager. GSREA has ten experienced real estate and investment professionals on staff, three of whom have prior commercial real estate loan workout experience. GSREA benefits from its affiliation with GP with respect to real estate markets information flow, CDO administration, and back office support. Generally, GSRE investments are serviced by rated CMBS servicers. For more details, please refer to the Derivative Fitch Asset Manager Profile on Guggenheim Structured Real Estate available on the Derivative Fitch web site www.derivativefitch.com.

Performance Summary:

As of the August 2007 trustee report, the modeled as-is poolwide expected loss (PEL) remains unchanged at 22.500%. The PEL covenant is based on a weighted-average spread (WAS) and PEL matrix. The matrix provides between 5.000% and 12.000% of cushion to the as-is PEL. This reinvestment cushion represents below average cushion at the lower WAS levels of the matrix, and average cushion at the upper WAS levels of the matrix, relative to recent Fitch rated CRE CDOs. Based on the current weighted average spread (WAS) of 2.48%, the deal has 11.750% cushion.

Since the last review, one land loan (7.7%), an A-note secured by a master planned development, has been added to the CDO. The repaid CRE loans include the La Quinta Portfolio, Affina NYC Portfolio, ESA Portfolio and Kettering Tower.

In addition to the above referenced CRE loan, portions of the class L notes from the GSMS 2007-EOP (7.9%) CMBS transaction, rated 'BB+' by Fitch, and the class F notes from the GUGH 2006-3 CRE CDO (3.4%), rated 'BB' by Fitch, were added to the CDO. Since the last Fitch review, the amount of securities and bank loans has grown to 56.0% from 45.1% of the CDO. The current weighted average rating factor (WARF) for the securities and bank loans is in the 'BB/BB-' category.

The CDO is in compliance with all reinvestment covenants. Although the weighted average coupon (WAC) has remained the same (6.58%) since the last review, the WAS has increased to 2.48% from 2.44%. In addition, the weighted average life (WAL) has increased to 4.1 years from 3.0 years, continuing to imply that the pool composition is likely to fully turn over during the reinvestment period.

The over collateralization (OC) and interest coverage (IC) ratios of all classes have remained above their covenants, as of the August 2007 trustee report.

Collateral Analysis:

Based on the invested amount, the pool is comprised of CRE bank loans (23.7%), CMBS (22.6%), CRE mezzanine loans (18.0%), CRE whole loans/A-notes (16.6%), CRE CDOs (9.7%) and CRE B-notes (9.4%). GSREA typically invests in the middle of the capital structure such that there are multiple layers of subordinate lenders providing insulation beneath its position.

Since the last Fitch review, the percent of hotel properties has decreased to 12.1% from 23.9% of the CDO. The percentage of condominium conversions has remained the same (8.3%). Since the last review one land loan, which is an A-note in a master planned development (5.1%), has been added to the CDO. The land development property is a 513.2 acre land parcel located adjacent to the Orange County Convention Center in Orlando, FL. The proposed mixed use development benefits from flexible entitlements and an up-front interest reserve that provides for interest payments through the extended maturity date, calculated at the interest rate cap. Office properties remain the largest percentage of traditional property types (12.9%, down from 19.8%), followed by retail (3.0%, which remained the same). Property type covenants are within their covenanted guidelines.

The pool is considered concentrated, relative to other recently Fitch rated CRE CDOs. Based on the CDO collateral as of the August 20, 2007 trustee report, the loan diversity index score is 556. The largest two loans represent 7.9% and 7.7% of the current collateral amount, respectively. The CDO is well within all of its geographic covenants with the two largest concentrations being New York (7.8%) and Florida (7.7%).

For a summary of the Fitch Loans of Concern and the 10 largest loans, please refer to the Guggenheim 2006-4 CREL Surveyor Snapshot on the Derivative Fitch web site, which will be available beginning September 21, 2007.

Rating Definitions:

The ratings of the classes S, A-1, A-2, and B notes address the likelihood that investors will receive full and timely payments of interest, as per the governing documents, as well as the aggregate outstanding amount of principal by the stated maturity date. The ratings of the class C, D, E, F, G and H notes address the likelihood that investors will receive ultimate interest and deferred interest payments, as per the governing documents, as well as the aggregate outstanding amount of principal by the stated maturity date.

Ongoing Surveillance:

Fitch will continue to monitor and review this transaction and will issue an updated Snapshot report after each committeed review. The surveillance team will conduct a review whenever there is approximately 15% change in the collateral composition or semi-annually. For more detailed information, please see the Guggenheim 2006-4 CREL Surveyor Snapshot on the Derivative Fitch web site at www.derivativefitch.com. For more information on the Fitch Rating Methodology for CREL CDOs, see 'Rating Methodology for U.S. Commercial Real Estate Loan CDOs' dated Sept. 25, 2006, which is also available at www.derivativefitch.com.

Fitch's rating definitions and the terms of use of such ratings are available on the agency's public site, www.derivativefitch.com. Published ratings, criteria and methodologies are available from this site, at all times. Fitch's code of conduct, confidentiality, conflicts of interest, affiliate firewall, compliance and other relevant policies and procedures are also available from the 'Code of Conduct' section of this site. Fitch means Fitch, Inc., Fitch Ratings, Ltd. and their subsidiaries including Derivative Fitch, Inc. and Derivative Fitch Ltd. and any successor or successors thereto.