Re: Is RCU now possible?

[ian007%mac.com@localhost]

On Jul 30, 2014, at 1:55 PM, Dennis Ferguson wrote:

> I was wondering if it is now possible to have a full RCU
> implementation in the kernel?
>
> I realize there used to be patent issues with this.  Wikipedia
> lists the following US patents:
>
>         5,608,893
>         5,727,209
>         6,219,690
>         6,886,162
>
> When I look at these, however, the first patent was filed in
> 1993 and should now be expired while the remaining three (according
> to google patents) seem to have lapsed around 2010 when IBM failed
> to pay the maintenance fee to extend them.
>
> Is there anything else?
>
> Dennis Ferguson

DISCLAIMER: You should neither take any actions nor refrain from any  
actions based on this general information.

You can obtain information regarding a status of a patent or patent  
application from the U.S. Patent and Trademark Office's Public PAIR  
(Patent Application Information Retrieval) website:

http://portal.uspto.gov/pair/PublicPair

Public PAIR is where the following information was obtained.

Regarding U.S. Pat. No. 5,608,893:
    Filing or 371 (c) date:  06-07-1995
    Issue Date of Patent:  03-04-1997
    Status:  Patent Expired Due to NonPayment of Maintenance Fees  
Under 37 CFR 1.362
    Status Date:  03-30-2009

Regarding U.S. Pat. No. 5,727,209:
    Filing or 371 (c) date:  11-01-1996
    Issue Date of Patent:  03-10-1998
    Status:  Patent Expired Due to NonPayment of Maintenance Fees  
Under 37 CFR 1.362
    Status Date:  04-05-2010

Regarding U.S. Pat. No. 6,219,690:
    Filing or 371 (c) date:  11-01-1996
    Issue Date of Patent:  04-17-2001
    Status:  Patent Expired Maintenance Fees Under 37 CFR 1.362
    Status Date:  05-18-2009

Regarding U.S. Pat. No. 6,886,162:
    Filing or 371 (c) date:  07-31-1998
    Issue Date of Patent:  04-26-2005
    Status:  Patent Expired Due to NonPayment of Maintenance Fees  
Under 37 CFR 1.362
    Status Date:  05-25-2009

Please keep in mind that these are U.S. patents.

Cheers,
   Ian Fink