(Adds comment from Greek government official and detail on German participants and on Delta Lloyd saying it won't participate unless all others do so.)

THE EVENT: A crucial deadline is approaching as Greece seeks to get commitments by its bondholders to agree to a debt-restructuring plan that will involve big losses on their holdings.

The restructuring involves debt worth EUR206 billion in the hands of the private sector, although the current offer is extended to holders of EUR177 billion of bonds under Greek law. Greece needs to secure at least 90% of that for the bond exchange to proceed on a voluntary basis.

If under 90% of holders participate, Greece has the option of invoking collective action clauses to force remaining holders to accept the deal. But for that to happen, at least half of the bond holders must participate in a related vote and at least two-thirds of them should vote in favor of the bond-swap terms.

THE DEADLINE: Bondholders have until 2000 GMT Thursday to accept the deal, which will result in the exchange of existing bonds for new ones with a face value slashed by 53.5%.

The Greek government will announce the results at 0600 GMT Friday, a person close to the finance ministry said.

Late Thursday, a Greek government official said that more than 75% of private holders of Greek debt have indicated they plan to participate. "Yesterday evening the participation rate exceeded 75%," the official said. "At the moment, it appears that we will exceed even the optimistic scenario."

Charles Dallara, managing director of the IIF, also said Thursday that he is "quite optimistic" that the deal will come together in the final hours. He expressed optimism that participation will be "very, very high."

Officially, as of late Wednesday, about 52% of the EUR206 billion ($271 billion) in bonds up for restructuring had been pledged.

THE IMPORTANCE: The bond swap is an integral part of a second, EUR130 billion bailout loan for Greece that will keep it from becoming the first euro-zone member to default when a EUR14.5 billion bond redemption comes up March 20.

DETRACTORS: Some bondholders, particularly hedge funds, are likely to reject the nation's debt-restructuring plan, gambling on being repaid for their bonds in full--or at least more than everyone else. According to some sources, the move could back-fire and result in bondholders losing more money than they would have done under the swap agreement.

WRITE-DOWNS: Many bondholders have already set aside provisions covering at least the level of losses agreed by the IIF, limiting the financial impact on them if the losses were to deepen. The participation rate will be calculated on the nominal, or face, value of the holdings.

Here are highlights of bank comments from financial companies ahead of the deadline. Banks and insurers in France, Germany and Greece have the majority of the holdings:

STEERING COMMITTEE:

*There were 13 banks, insurance firms and funds participating in the steering committee that negotiated the terms of the debt restructuring under the IIF, which represents some 450 financial institutions. They vowed to participate in a statement earlier this week.

Steering committee companies and others officially pledging to participate, according to the IIF, as of Wednesday: Ageas NV (AGS.BT), Allianz SE (ALV.XE), Alpha Bank AE (ALPHA.AT), AXA SA (CS.FR), Banque Postale, BNP Paribas SA (BNP.FR), CNP Assurances (CNP.FR), Commerzbank AG (CBK.XE), Credit Agricole SA (ACA.FR), Credit Foncier, DekaBank, Deutsche Bank AG (DB), Dexia SA (DEXB.BT), Emporiki Bank of Greece SA (TEMP.AT), Eurobank EFG (BEUR.UR), Assicurazioni Generali SpA (G.MI), Greylock Capital Management, HSBC Holding PLC (HBC), ING Bank, Intesa Sanpaolo SpA (ISP.MI), Landesbank Baden-Wurttemberg, KBC Group NV (KBC.BT), Marfin Popular Bank PCL (CPB.CP), Metlife, National Bank of Greece SA (ETE.AT), Piraeus Bank, Royal Bank of Scotland Group PLC (RBS), Societe Generale SA (GLE.FR) and UniCredit SpA (UCG.MI).

ADDITIONAL BANK/INSURER COMMENTS:

GERMANY:

*Allianz SE (ALV.XE) said Wednesday it will take part in the swap, which it said was economically viable for the insurance company. It said it held bonds with a nominal value of about EUR1.3 billion at the end of 2011.

*Commerzbank, which was on the IIF participation list Monday, holds about EUR3 billion in Greek sovereign debt in nominal terms.

*Deutsche Bank, which was on the IIF participation list Monday, holds about EUR1.5 billion in Greek government debt in nominal terms.

*DZ Bank said Wednesday the bank will participate, along with all other holders of Greek sovereign debt within the cooperative bank sector. The sector includes, among others, asset manager Union Investment and insurer R+V. The bank holds around EUR1.15 billion in Greek sovereign debt, according to a Dow Jones Newswires calculation.

*Helaba said it will participate in the debt swap. The bank holds EUR85 million in Greek sovereign debt nominal value at the end of 2011.

*DekaBank has said it will partipate in swapping Greek sovereign debt; it holds around EUR100 million based on nominal value.

*Hypo RE's FMS Wertmanagement holds some EUR7.2 billion in Greek sovereign debt, EUR1.6 billion in loans, bonds of Greek companies. FMS hasn't officially decided yet whether to take part. However, it is expected to do so, two people familiar with the matter told Dow Jones Newswires.

*KfW Bankengruppe, the German government's development bank, will participate, Chief Executive Ulrich Schroeder told reporters, adding that sentiment about private-sector participation in the swap has "dramatically changed" in the past few days. It has about EUR250 million in nominal value.

*LBBW said Wednesday it will participate in the PSI. It held around EUR628 million in Greek sovereign debt at the end of September.

*Munich Re AG (MUV2.XE) will participate, a spokeswoman said Wednesday. Munich Re held Greek sovereign debt with a nominal value of EUR1.59 billion at the end of September.

*WestLB's EAA bad bank said it is participating in the debt swap. It still holds EUR900 million in Greek government bonds in nominal value. WestLB itself no longer holds Greek sovereign debt.

*WGZ-Bank said it will take part. The bank holds EUR530 million in Greek sovereign debt nominal value as of September 2011.

GREECE:

*Alpha Bank, Eurobank, Piraeus Bank and National Bank of Greece are all on the steering committee and Monday vowed to participate.

*On Wednesday, members of the Private Creditor-Investor Committee for Greece, who hold 39.3% of the eligible bonds, or EUR81 billion, said they intend to participate in the bond exchange.

The institutions that comprise the PCIC are Emporiki Bank (TEMP.AT) and Marfin Popular Bank (CPB.CP), along with Alpha Bank, Eurobank, Piraeus Bank and NBG.

ITALY:

*UniCredit SpA (UCG.MI): Italy's second-largest bank by market value said it will participate in the bond swap. As of the end of the third quarter of 2011, the nominal value of its holdings was EUR541 million.

NORDICS:

*Jyske Bank A/S (JYSK.KO) is the largest holder of Greek sovereign debt in the Nordic region, with bonds with a nominal value of around EUR68 million. It hasn't stated its intentions ahead of Thursday's restructuring agreement. Other Nordic banks hold even smaller levels, or no Greek debt at all, as the region's banks have so far managed to limit their exposure to Southern Europe's troubled economies.

PORTUGAL:

*Banco BPI SA (BPI.LB). Will participate. As of Oct. 31, the nominal value of its Greek holdings was EUR480 million.

*Banco Comercial Portugues SA (BCP.LB), with nominal holdings of about EUR719 million, said it will participate.

*State-owned Caixa Geral de Depositos, with EUR133 million exposure, will participate.

NETHERLANDS:

Delta Lloyd NV (DL.AE): The Dutch insurer said Thursday that it isn't planning to participate in a debt-restructuring plan for Greece, because it has principal objections. The CEO said he will only participate if all private bondholders participate. This will only happen when less than 90% of holders join the exchange, as it would invoke collective action clauses that would force the remaining holders to accept the deal. "We think everyone should participate," Hoek said. Delta Lloyd holds EUR71 million in Greek government bonds in nominal value.

UK:

*Royal Bank of Scotland Group PLC (RBS) was on the original IIF participation list. The bank said its nominal holdings were GBP1.6 billion.

*Standard Chartered PLC (STAN.LN) said it had no exposure to Greek sovereign debt.

*Lloyds Banking Group PLC (LYG) said it has no exposure to Greek sovereign debt.

*Barclays PLC (BCS) declined to comment on the PSI and simply said its exposure to Greek sovereign debt was "minimal."